Board index » MDC Worlds » Robotech® - The Shadow Chronicles® - Macross II®

 


Post new topic Reply to topic
Author Message
Unread postPosted: Sat Sep 07, 2019 2:30 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Well... from the RPG's perspective, we could say they have a reconnaissance craft in the VEFR-1 via the UEEF Marines book's insistence that the Expeditionary Forces marines continued to use the VF-1. I know they slightly tweaked the name in the RPG, but it was designated as a multi-role electronic warning and reconnaissance craft originally.

But how many VEFR-1s are there realistically in the UEEF inventory? How many VF-1s are realistically in the UEEF inventory? By 2022 or by 2030 or even by 204x. They aren't producing more, and attrition is going to happen one way or the other (either from combat or lack of spare parts).

Seto wrote:
TBH, I'm not sure I would call what we saw in RTSC "reconnaissance" since they appear to have been flying a BARCAP op instead of actually scouting anything. The Shadow Fighter would make a pretty awful reconnaissance aircraft since most of its sensors are passive and, its main radar field-of-view is typically fighter-esque, and its other sensors are fairly ill-suited to the task.

That's how the pilots see it, I won't argue if it is more properly something else.

The Shadow Fighter could still carry a pod(s) with better sensors to perform the mission (obviously it wasn't used in TSC), one that could be contained in a gunpod casing for ease of use by the battloid (VEFR-1 does this to IINM). Or there could be a variant of the Alpha/Beta with better sensors for the task (while OSM, Imaifiles does have a recon Legoiss variant pg93 M4-07 around this area other bolt-on packages also appear, indicating that OSM-ly a variant was considered during pre-production, though I don't know if I'd go with what is depicted), but this gets into the whole we don't know what they actually use for these Planetary Survey Missions. For a planetary survey (or even recon) mission passive sensors are not a bad thing, its more their resolution I would be concerned with.

Seto wrote:
but it was always supposed to be something that was designed alongside the Alpha.

In the OSM yes all three troublesome designs in the story are that way, however in RT this doesn't appear to be the case. The Alpha is a ~30 year old design, with the oldest known cyclone dates I could find coming it at 1/2 its age and the Beta being added late in the process. Admittedly the Cyclone might have an unknown precursor in the UEEF. Then again the Alpha seems to always be "new" in the comics (2014-ish, 2030-ish, 2038-ish), so maybe they kept changing things requiring changes to the design (ala F-22) and finally someone said "enough".

Seto wrote:
... there doesn't seem to be a separate planetary defense group, and the one time we see one of their surface installations attacked they do such a rubbish job of defending it that it would tend to bear out the idea that they're not equipped for planetary defense.

Not equipped for planetary defense? I would disagree, I think it would be more accurate to say they aren't organized for planetary defense, and there is a difference. You're referring to Edwards escape from Tiresia? Or the ASC's defense of Earth?

Seto wrote:
It doesn't so much point to a change in doctrine, IMO, as it does the uncomfortable realization that ships designed around pre-1st War assumptions about space combat proving to be useless.

If their assumptions are proving useless, then that means they have to shift their doctrine from changing the levels of emphasis on "ship-ship combat" and "planetary assault". It might not be radical doctrine change, but it is doctrine change.

Seto wrote:
Mind you, the Alpha's main problem here isn't a delta-v issue so much as an inability to even reach altitudes where its lacking endurance could become an issue in the first place.

As I've said in the past, this doesn't make sense. The Delta-V determines how far and how fast you can go on pure rocket power. This is also compounded by a lack of useful statistical data that could put this to bed (ex. propellant mass, burn time, etc). You'd almost thing HG is avoiding quantifying things in writing or something ("short legs" in space is relative since we don't know what they conceive of as "short" for example) or doesn't realize that what they state is not necessarily supported by animation (even if we ignore TSC, which clearly shows they weren't paying attention to details).


          Top  
 
Unread postPosted: Sat Sep 07, 2019 5:13 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
But how many VEFR-1s are there realistically in the UEEF inventory? How many VF-1s are realistically in the UEEF inventory? By 2022 or by 2030 or even by 204x. They aren't producing more, and attrition is going to happen one way or the other (either from combat or lack of spare parts).

As many as the GM says?

Really, since VEFR-1's aren't front line combat aircraft their attrition rates should be significantly lower than the regular VF-1 or Alpha. Spare parts shouldn't be too big of an issue, given that the RPG's stance is the UEEF Marines used the VF-1 for decades and most of their parts are common.

Spoiler:
Even in the Macross series, the VEFR-1's Block 6+ successor design (VE-1) remained in service for decades as the rugged, rock-solid, go-to ELINT/AWACS VF until the VE-11 came out in the 2030s.




ShadowLogan wrote:
That's how the pilots see it, I won't argue if it is more properly something else.

If they hadn't gone to ground to avoid the Invid patrol, you could've called it reconnaissance-in-force... it's just one bit of dialog among many in that movie that doesn't really make sense.



ShadowLogan wrote:
The Shadow Fighter could still carry a pod(s) with better sensors to perform the mission (obviously it wasn't used in TSC), one that could be contained in a gunpod casing for ease of use by the battloid (VEFR-1 does this to IINM).

Granted, and there are real-world equivalents to this exact thing... but the Alpha is a pretty unfriendly design to that kind of modular equipment. Normally a TARPS has to be mounted centerline so it has an unobstructed field of view. The Alpha and Shadow Fighter don't have adequate ground clearance for that.

The VEFR-1's gear is straight-up built into the aircraft's arms and isn't removable. The OSM line art doesn't even have hands.



ShadowLogan wrote:
Or there could be a variant of the Alpha/Beta with better sensors for the task (while OSM, Imaifiles does have a recon Legoiss variant pg93 M4-07 around this area other bolt-on packages also appear, indicating that OSM-ly a variant was considered during pre-production, though I don't know if I'd go with what is depicted), but this gets into the whole we don't know what they actually use for these Planetary Survey Missions. For a planetary survey (or even recon) mission passive sensors are not a bad thing, its more their resolution I would be concerned with.

There is that, yeah... though I don't see how this thing could even transform given where that radome and other pods are mounted. :|

You generally don't want to use passive sensors for reconnaissance or survey operations because then you miss a lot of information.



ShadowLogan wrote:
Admittedly the Cyclone might have an unknown precursor in the UEEF. Then again the Alpha seems to always be "new" in the comics (2014-ish, 2030-ish, 2038-ish), so maybe they kept changing things requiring changes to the design (ala F-22) and finally someone said "enough".

Aren't there several such precursors in the UEEF Marines book and Imai Files?



ShadowLogan wrote:
Not equipped for planetary defense? I would disagree, I think it would be more accurate to say they aren't organized for planetary defense, and there is a difference. You're referring to Edwards escape from Tiresia? Or the ASC's defense of Earth?

The former, the latter case wasn't UEEF.



ShadowLogan wrote:
As I've said in the past, this doesn't make sense. The Delta-V determines how far and how fast you can go on pure rocket power.

It actually makes sense... the Alpha doesn't have the propellant or thrust to achieve a ballistic ascent to LEO, and its aerodynamic performance and turbine efficiency isn't good enough to get up there under a less ballistic trajectory. Its engines are very small, and the thrust isn't that high.



ShadowLogan wrote:
This is also compounded by a lack of useful statistical data that could put this to bed (ex. propellant mass, burn time, etc). You'd almost thing HG is avoiding quantifying things in writing or something ("short legs" in space is relative since we don't know what they conceive of as "short" for example) or doesn't realize that what they state is not necessarily supported by animation (even if we ignore TSC, which clearly shows they weren't paying attention to details).

In all fairness, that's not really on them... that's on the OSM. The AFC-01 Legioss wasn't intended to be a space fighter. It wasn't even intended to be a main mecha of the show past a certain point in development, before Gakken stuck their oar in and said they wanted to get a piece of Takatoku's action. It was just supposed to be that plane that Stick would crash in the first episode that would get him and his titular MOSPEADA to Earth to fight the good fight. The only thing the Legioss was ever intended to do in space was launch from the Space Fortress Carriers and blaze a trail for the ships it was escorting during the landing op. The reason it couldn't make it to orbit under its own power was that it wasn't that much better than modern fighters in terms of performance.

The only thing you can really accuse Robotech's writers of doing here is trying to make it into something it's not. That's where the problems came in. They tried to make it into an all-regime VF like the Macross's VF-1.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Sat Sep 07, 2019 7:06 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
it's just one bit of dialog among many in that movie that doesn't really make sense.

I think you mean to write: " it's just one bit among many in that movie that doesn't really make sense." ;)

Seto wrote:
The Alpha and Shadow Fighter don't have adequate ground clearance for that.

Only if one is dead set that they have to use F-mode for take-offs and landings you mean.

Seto wrote:
There is that, yeah... though I don't see how this thing could even transform given where that radome and other pods are mounted.

The only part(s) that actually may have to go for transformation IMHO is the leg pods.

The Radome could in theory move with the arm, maybe even a bit of additional movement. I know I've seen art for a F-Mode Alpha with radome (not sure if its fanart, or lineart).

The TLEAD masts on the back might have to go, but they might still be usable depending on how they are mounted. Since its a pre-production they could go.

Seto wrote:
Aren't there several such precursors in the UEEF Marines book and Imai Files?

I thought Marines Cyclones where not intended for "emergency" use like the VR-041/052, that and no dating is given. Other options would require knowing if they could be collapsed to fit in the bay (and be light enough as the bay has a stated weight limit).

Seto wrote:
The former, the latter case wasn't UEEF.

Is it actually fair to count it as such though, I mean how many defense organizations consider a scenario where the enemy is fighting outward from your base? Or a simultaneous mass defection?

Seto wrote:
It actually makes sense... the Alpha doesn't have the propellant or thrust to achieve a ballistic ascent to LEO, and its aerodynamic performance and turbine efficiency isn't good enough to get up there under a less ballistic trajectory. Its engines are very small, and the thrust isn't that high.

We know the Alpha has plenty of thrust to achieve a ballistic trajectory. Propellant capacity possibly, but to make that claim we'd actually have to have hard numbers to determine that (something that is lacking).


          Top  
 
Unread postPosted: Sat Sep 07, 2019 10:42 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
Seto wrote:
it's just one bit of dialog among many in that movie that doesn't really make sense.

I think you mean to write: " it's just one bit among many in that movie that doesn't really make sense." ;)

Yes, I suppose I shouldn't limit it to the dialog.



ShadowLogan wrote:
Seto wrote:
The Alpha and Shadow Fighter don't have adequate ground clearance for that.

Only if one is dead set that they have to use F-mode for take-offs and landings you mean.

Well, neither version of the Ikazuchi-class is going to be all that friendly to the idea... since the launch bays for the TV and "Movie" versions are different but equally cramped.

The point about mode is technically valid though, since they launch in B mode in the series and F in the movie.



ShadowLogan wrote:
The Radome could in theory move with the arm, maybe even a bit of additional movement. I know I've seen art for a F-Mode Alpha with radome (not sure if its fanart, or lineart).

If it's the piece I've seen, it's fanart... an attempt to graft the Aegis Pack used by the RVF-171 and RVF-25 in Macross Frontier onto an Alpha. The same site had a number of other odd things like bad recolors of several Macross mecha claiming to be Shadow versions of various Robotech mecha. (e.g. the Destroid mode of the VB-6 Konig Monster as a "Shadow Monster")



ShadowLogan wrote:
Seto wrote:
Aren't there several such precursors in the UEEF Marines book and Imai Files?

I thought Marines Cyclones where not intended for "emergency" use like the VR-041/052, that and no dating is given. Other options would require knowing if they could be collapsed to fit in the bay (and be light enough as the bay has a stated weight limit).

It was a thought.



ShadowLogan wrote:
Seto wrote:
The former, the latter case wasn't UEEF.

Is it actually fair to count it as such though, I mean how many defense organizations consider a scenario where the enemy is fighting outward from your base? Or a simultaneous mass defection?

If you're holding a bunch of enemy automatons the way the UEEF was at the time?



ShadowLogan wrote:
We know the Alpha has plenty of thrust to achieve a ballistic trajectory. Propellant capacity possibly, but to make that claim we'd actually have to have hard numbers to determine that (something that is lacking).

Not for any considerable distance... it's a blocky little plane with poor aerodynamics, it's not going to get very far in ballistic flight and its turbines just aren't big enough or powerful enough to provide the kind of compression you need to operate in the upper atmosphere. The VF-1 only makes it work by having an entirely separate set of electrically-driven ram-air precompressors driving up the main turbine's compression ratio.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Sun Sep 08, 2019 11:46 am
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
It was a thought.

And a valid one. I think the VR-02x series isn't going to be used (space cyclones?), leaving just the VR-01x series or the Cyclone derived nt-PA. Neither seem suited to use as an emergency vehicle (as Scott calls the VR-052 in Ep61, actually he calls it "new emergency vehicle"). The nt-PA would need to be made to fit the available space, and the VR-01x series doesn't seem to fit either given it's designed for air-drops (rather useless ability to the pilot). The MR-40 is another option potentially (no firm dates either or mention of use of an emergency vehicle so it might not even be able to compress down for the storage bay).

Seto wrote:
If you're holding a bunch of enemy automatons the way the UEEF was at the time?

I don't think this qualifies as "planetary defense" as they really aren't defending the planet/facility from a force approaching from space. Those troops are already there, its more like the Inorganics are like "rioting prisoners" or launching a surprise diversionary attack than an invasion force. It also doesn't help the directing intelligence (Edwards) has the UEEF playbook and could deploy them for maximum effectiveness.

Seto wrote:
Not for any considerable distance... it's a blocky little plane with poor aerodynamics, it's not going to get very far in ballistic flight and its turbines just aren't big enough or powerful enough to provide the kind of compression you need to operate in the upper atmosphere. The VF-1 only makes it work by having an entirely separate set of electrically-driven ram-air precompressors driving up the main turbine's compression ratio.


The problem is you assume the Alpha has to operate like the VF-1 in this respect, the Alpha could switch its propulsion system over to space-mode earlier (since we know the engines can operate in the vacuum of space, meaning they can operate in atmosphere). This approach is obviously more propellant intensive since it can't use the atmosphere as a propellant source, but it removes the engine issue and at 30km (and above) the Alpha's aerodynamics are less of an issue than they are closer to sea level (where it is depicted most of the time in the show) given pressure at that altitude is ~1/100th that of sea level requiring it to stay aloft on pure engine power (which given its T/W of better than 1 it should be able to do as long as the propellant holds out).

Which still brings us back to the need to quantify certain values. At least if we want to make sure the "background" info is consistent with the depictions* (yes I know the Alpha does not technically do an Earth SSTO or sub-orbital) or what can be derived from those depictions. We really don't know how much propellant the Alpha (or Beta or Logan or AGAC) carry, nor do we know their burn-time or how efficient the engine is (any two of these could derive the rest for the Alpha and maybe the Beta, but the ASC units require a bit more data AFAIK). Such information could also tell us how well it would operate at the Moon or Mars (or other large moon or dwarf planet), since technically those bodies don't have the same requirements to get into orbit as Earth, allowing for more story options w/n the Solar System ("space pirates" or Zent/RM holdouts).

*given the changing nature of the Shadow Device between the 85ep animation and TSC, they would have been depicted differently in terms of performance so should be evaluated separately. TSC can actually use the Shadow Device to impact performance (via the ability to hide mass to some degree given N-S warhead scene at the end of Prelude), where the 85ep/GCM depictions could not.


          Top  
 
Unread postPosted: Sun Sep 08, 2019 11:21 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
The problem is you assume the Alpha has to operate like the VF-1 in this respect, the Alpha could switch its propulsion system over to space-mode earlier (since we know the engines can operate in the vacuum of space, meaning they can operate in atmosphere). This approach is obviously more propellant intensive since it can't use the atmosphere as a propellant source, but it removes the engine issue and at 30km (and above) [...]

At that point, you're just trading one set of problems for another set that's equally severe.

Switching the engines over to space mode earlier will mitigate the problems caused by the comparatively low (read: "closer to real world") compression ratios of the fighter's turbine engines, but you're going to eat through the already limited supply of propellant even faster than you would in space because you're contending with both atmospheric drag and gravity. The atmospheric operating limit of the Alpha's turbines is 18km, from the OSM spec... you'd need to be burning propellant just to get to 30km, never mind above it. The Alpha doesn't have the luxury of the VF-1's superconducting ram air compressors in the intakes and (if you buy Master File's take) the ability to switch to running as an actual ramjet or scramjet at sufficiently high altitudes and speeds.

My guess would be, in-universe, the ability to get hypersonic above 30km and fly all the way to the edge of space over an Earth-type planet unassisted was deemed unnecessary or too expensive for post-1RW designs.



ShadowLogan wrote:
Which still brings us back to the need to quantify certain values. At least if we want to make sure the "background" info is consistent with the depictions*

There's not really any good way to go about it, since there's virtually no reliable data about the mecha of Southern Cross and MOSPEADA's creators neglected to give us anything so handy as an internal tank capacity. From the cutaways, it's questionable where the Legioss would even keep its space-use propellant.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Tue Sep 10, 2019 12:40 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
but you're going to eat through the already limited supply of propellant even faster than you would in space because you're contending with both atmospheric drag and gravity. The atmospheric operating limit of the Alpha's turbines is 18km, from the OSM spec... you'd need to be burning propellant just to get to 30km, never mind above it.

30km is the fighter mode ceiling as described in the Infopedia, AotSC, and 2E RPG. Nothing in these sources indicates how this is being performed (pure jet or rocket power) or other limitations (which using rocket power would require I would think since it would limit operating time).

As for limited propellant, that actually is relative based on the efficiency of the engine. Which we don't have, though we can make certain statements I think that the RT-Alpha is more efficient than its OSM counterpart. (See below)

Drag (air/gravity) yes potentially an issue, but perhaps not as much as one might think (it amounts to 1.5-2kps but that is from a surface launch, given we're talking about switching over at 18 or 30km that value will be less owing to a less dense atmosphere for the rocket portion of the flight).

Seto wrote:
My guess would be, in-universe, the ability to get hypersonic above 30km and fly all the way to the edge of space over an Earth-type planet unassisted was deemed unnecessary or too expensive for post-1RW designs.

While that is possible, what would be their basis for deeming it unnecessary in-universe? The Southern Cross might be able to justify it (we'll use conventional fighter or missiles), but the UEEF is going to have a lot harder time given all the unknowns they have to deal with (do they have planetary data on Tirol, or any other habitable world?).

I don't think we can play the cost card, not when they went with the most "expensive" option to address the issue for solo operations at different points in time (ie Beta).

Seto wrote:
There's not really any good way to go about it, since there's virtually no reliable data about the mecha of Southern Cross and MOSPEADA's creators neglected to give us anything so handy as an internal tank capacity. From the cutaways, it's questionable where the Legioss would even keep its space-use propellant.

Even if we had more fleshed out stats for the later sagas, all three sagas would need to make changes to some of them which will impact some derived figures given HG has changed some things (most notable the fuel source) from the OSM.

Ex. The OSM VF-1 carries ~119.85kg of Slush-H2, for an Isp* of ~75,591sec for a Delta-V of 6.671kps (dry state). Changing NOTHING else (thrust, burn-time, Volume) in the RT-version (per 2E PB RPG) of the VF-1 using SLMH** it would carry 1,198.5kg of SLMH, but end up with an Isp of ~7,559sec with a Delta-V of 6.415kps (dry state). Even though SLMH is more energy dense than Slush-H2, one should be wondering what is going on here since the SLMH should be giving better performance. There are ways to "fix" it, but they all involve changing other values (ex. burn time, trading fuel 1:1 in mass instead of volume, some mix of the two) in order to get them to make some sense. Of course HG can go back to the OSM fuel for TMS (who knows with TRM), but not with NG.

And it gets even worse with Protoculture if we consider that it is more energy dense than an undefined form of nuclear energy. This means that while the OSM Legoiss may have issues getting into orbit, the Alpha's more energy dense fuel source is not going to be as limited from the same mass of propellant. IIRC the Legoiss is powered by H2 Fuel Cells powering electrical rocket engines, the RT-Alpha is powered by something comparable/better than Nuclear Fusion (since PC fueled mecha replaced fusion fueled mecha), so it should have better performance in space-related functions even if we hamstring it to OSM thrust levels.

We know the Alpha has some areas that might work for propellant storage if we use the cutaways, the Beta likely has various places to given its considered a big tank. Alternatively we could treat the PC canisters as holding sole reaction mass, but for the 32cells of the Beta to even attempt the SSTO-Moon trajectory we see in Ep85/TSC would require it's engines to be at-least x14 more efficient than the OSM-VF-1, assuming an Apollo level trip time (reality is the trip time is likely shorter, so need more). Assuming the Alpha's engines are similarly as efficient as the Beta in this scenario, it can do SSTO w/room to spare on pure rocket power (no assist from air breathing engines) using just the 16cells and actually the Beta becomes unnecessary from this position (the stack has less Delta-V than the solo Alpha-H/I in this scenario). This assumes the 2.1kg mass of the canisters I calculated years ago holds (as I doubt HG will want to quantify the mass of the contents of those cells, or provide density of PC fuel, etc), it also dedicates all 2.1kg to use (for ease of use, so actual values here are going to be a bit off). The Alpha's engines can drop to as low as x6-7 and still do SSTO (barely) on 16cells. For OSM compression, even if we assume the Legois/Tlead engine efficiencies are equal to an OSM VF-1 in a similar scenario the Tlead couldn't do SSTO shown (much less fly to the Moon as an implied destination) on pure rocket power (a VF-1 type profile for SSTO sure, but it isn't getting to the Moon).

The Logan's small size makes it very difficult compared to the AGAC. If the 2E RPG is to be believed here, these two mecha also are several times more fuel efficient than the VF-1 given their operating times coupled with their small size.

*Specific Impulse, efficiency value of a rocket engine
**assuming it is x12 more dense than LH2, though the density I've seen expresses it as x12-13. Slush-H2 is 20% more dense than LH2, or 1/10th that of SLMH estimate on the low end.


          Top  
 
Unread postPosted: Tue Sep 10, 2019 3:33 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
30km is the fighter mode ceiling as described in the Infopedia, AotSC, and 2E RPG.

It's not described as a service ceiling, just a speed at altitude...



ShadowLogan wrote:
Drag (air/gravity) yes potentially an issue, but perhaps not as much as one might think (it amounts to 1.5-2kps but that is from a surface launch, given we're talking about switching over at 18 or 30km that value will be less owing to a less dense atmosphere for the rocket portion of the flight).

It's still going to induce a measurable increase in fuel consumption, esp. given the Alpha isn't aerodynamically sound at those altitudes and would basically have to be flying on rocket thrust.



ShadowLogan wrote:
While that is possible, what would be their basis for deeming it unnecessary in-universe? The Southern Cross might be able to justify it (we'll use conventional fighter or missiles), but the UEEF is going to have a lot harder time given all the unknowns they have to deal with (do they have planetary data on Tirol, or any other habitable world?).

I don't think we can play the cost card, not when they went with the most "expensive" option to address the issue for solo operations at different points in time (ie Beta).

I think we explicitly CAN play the cost card, because cost was exactly the reason a fighter with capabilities similar to the VF-1's was passed over in favor of the Alpha. (The YF-4.)



ShadowLogan wrote:
Ex. The OSM VF-1 carries ~119.85kg of Slush-H2, for an Isp* of ~75,591sec for a Delta-V of 6.671kps (dry state). Changing NOTHING else (thrust, burn-time, Volume) in the RT-version (per 2E PB RPG) of the VF-1 using SLMH** it would carry 1,198.5kg of SLMH, but end up with an Isp of ~7,559sec with a Delta-V of 6.415kps (dry state). Even though SLMH is more energy dense than Slush-H2, one should be wondering what is going on here since the SLMH should be giving better performance.

This is a fairly easy-to-explain issue... which is down to a difference in technology between settings.

Robotech's mecha are using conventional, single-reaction thermonuclear fusion... they're using magnetic field pinches to fuse hydrogen into helium. The Macross OSM's reactors are a more advanced technology that use a gravitational pinch created using fold physics, making the fusion reaction significantly more efficient and energetic because more of the fuel is participating in the actual fusion reaction, and the intense gravitational compression ensures that more fuel participates in the fusion reaction and that the reaction itself follows chain reactions like the proton-proton chain, CNO cycle, etc. for greater energy yield from the same quantity of fuel.

Put simply, Robotech's VF-1 may be carrying ten times the mass of fuel that the OSM VF-1 is... but because its reactors are only 4.8% as efficient as the OSM VF-1's, ten times the fuel mass lasts less than half as long. So you see, I've actually been rather charitable to the Alpha in my computations because I've been assuming Macross OSM levels of efficiency (a 2083.333% leg up vs. the computable fuel efficiency of the Robotech setting's fusion engines). I do appreciate the amusing coincidence that 2083 is also the year the original MOSPEADA was set in.

Spoiler:
For those who haven't seen us chew this topic over in the past, here is the relevant data:

Macross OSM VF-1A-5 Valkyrie
Fuel: 1,410L of Hydrogen Slush
Fuel Mass: 119.85kg (@0.085kg/L)
Endurance: 700 hours / 29 days 4 hours (atmospheric), 10 minutes at maximum engine burn (space)

Robotech VF-1A
Fuel: 1,410L (assumed) of SLMH (RPG)
Fuel Mass: 1198.5kg (@0.85kg/L), mean density for liquid metallic hydrogen being 10x hydrogen slush's
Endurance: 336 hours / 14 days (atmospheric)




ShadowLogan wrote:
And it gets even worse with Protoculture if we consider that it is more energy dense than an undefined form of nuclear energy. This means that while the OSM Legoiss may have issues getting into orbit, the Alpha's more energy dense fuel source is not going to be as limited from the same mass of propellant. IIRC the Legoiss is powered by H2 Fuel Cells powering electrical rocket engines, the RT-Alpha is powered by something comparable/better than Nuclear Fusion (since PC fueled mecha replaced fusion fueled mecha), so it should have better performance in space-related functions even if we hamstring it to OSM thrust levels.

Now, it behooves us to remember that greater energy density does not in any way, shape, or form imply greater energy output or endurance on its own.

On its own, it sounds impressive to say that protoculture is more energy dense than nuclear fuels... but if you look at it rationally, it's an almost meaningless statement because the amount of energy you actually get out of it depends on how that energy is being harnessed and the quantity of fuel being used. One cubic centimeter of reactor-grade Uranium-238 in a fission reactor will yield slightly less energy than 100 cubic centimeters of deuterium in a fusion reactor. Take that same 100cc's of deuterium and burn it in a combustion engine and you'll get only a tiny fraction of the energy that would've yielded in the fusion reactor. Take that same U238 out of the fusion reactor and stick it in a RTG, and you'll get a long, slow, low output reaction instead of a faster, more energetic output of energy.

The Alpha has a very small quantity of protoculture - around 11 liters - in fuel cells. That points to a low output, high endurance powerplant. The output of the powerplant in the Alpha's case also has no direct relation to available engine power the way the VF-1's does, because they're effectively decoupled systems. Instead of having a reactor inside the engine heating intake air directly off the heat of the fusion reaction you've got a fuel cell outputting electricity that's being used to spin an electric turbine.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Wed Sep 11, 2019 12:01 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
It's not described as a service ceiling, just a speed at altitude...

It's the highest speed @ altitude listed though, making it a de facto "ceiling" in the stat blocks. Though given that the VF-1 and VF-9 can fly higher than the listed speed @ altitude it might not be a service ceiling at all, but it is the "ceiling" we have performance information for.

Seto wrote:
I think we explicitly CAN play the cost card, because cost was exactly the reason a fighter with capabilities similar to the VF-1's was passed over in favor of the Alpha. (The YF-4.)


Either Cost is a factor that the UEEF is considering OR it isn't. They can't have it both ways.

I'd be remiss to remind you that the Infopedia also adds complexity as a factor, it is also less agile than the Alpha, carries fewer missiles, and is bigger which are also sited. Complexity is revisited in the docking setup on the Alpha/Beta, and ironically the Alpha/Beta stack is BIGGER than a YF-4.

Seto wrote:
This is a fairly easy-to-explain issue... which is down to a difference in technology between settings.
...

FTS-comic has the VF-1 operating with a Reflex Furnance* (FTS chapter 4). While this might not be the same type of fusion system as the OSM, a RF being involved also means it isn't a pure "conventional" fusion setup as you suggest (yes, Infopedia/2E RPG limit it to fusion only, but they might not be going in-depth). I would also add that a "conventional" fusion drive setup in terms of efficiency IS closer to the OSM VF-1 than the RT VF-1 value (Isp's of ~100,000sec, I've seen it higher but this is the general value). This means that even if we go with the technology being different (and ignoring FTS), the derived values being considered are very inefficient for its type.

If we are allowing technology to be different between the settings (OSM v RT) in TMS, then it stands to reason that the same explanation could apply to NG vs GCM (and SDC:SC vs TRM). The OSM Legoiss/Tlead could use H2 fuel cells, but the RT Alpha/Beta are using PC in a Reflex Furnace. Per the RT Glossary definition of Reflex Furnace*, Shadow Devices are suggested to require this level of power output and we know the Alpha/Beta get Shadow Devices late in their life w/o mention of an powerplant change (ie removing the PC fuel cell for PC fueled Reflex Furnace). This means the Alpha/Beta aren't low-output/high-endurance system, but a high-output/high-endurance system by all indications.

So short of an official OSM/RT statement working out where the extra propellant is stored officially, the only known sources would be the HBT/PC canisters. Which means for them to do what we see, at minimum they have to be as efficient if not more so than what I stated previously based on their only known fuel source. The Alpha and Beta need not be as equally as efficient, but it stands to reason they should be similar/close given the available supply in RT.

*https://robotech.com/roboverse/term/reflex-furnace
also found in AoTSC pg140 (Glossary)

Seto wrote:
Now, it behooves us to remember that greater energy density does not in any way, shape, or form imply greater energy output or endurance on its own.

True, it comes down to how it gets utilized.

Seto wrote:
around 11 liters - in fuel cells

~15L if each canister is about equal to a can of motor oil (as described, so it might be more/less), which means 32oz/1qt US (assuming the size hasn't changed over time/region).


          Top  
 
Unread postPosted: Wed Sep 11, 2019 4:41 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
Either Cost is a factor that the UEEF is considering OR it isn't. They can't have it both ways.

"Cost" can be measured a lot of different ways... the actual monetary expense of the finished product, the man-hours and resources it takes to develop and/or manufacture the finished product, the monetary upkeep costs, the amount of time and resources needed for maintenance and repairs to keep it in service, etc.

You can have a design that is cheap to produce but hell to maintain due to bad design, or a design that's fiendishly overengineered but extremely cheap to maintain as a result. In this case, since the manufacturing has negligible costs in time or resources for actual people the complexity of the YF-4 design likely made it expensive (in resources and man-hours) to maintain because of its far higher performance than the Alpha.



ShadowLogan wrote:
Complexity is revisited in the docking setup on the Alpha/Beta, and ironically the Alpha/Beta stack is BIGGER than a YF-4.

That could be the easy go-to explanation for the Beta being a non-starter... too much added complexity running up the time and resource costs for maintenance.



ShadowLogan wrote:
FTS-comic has the VF-1 operating with a Reflex Furnance* (FTS chapter 4). [...]

You know as well as I do that this comic was written and published years before Harmony Gold's creative staff arrived at the decision to establish officially that the VF-1 used nuclear fusion instead of protoculture. That's the explanation for that line, not a new and exotic type of fusion power plant... nothing more or less than a retcon.



ShadowLogan wrote:
If we are allowing technology to be different between the settings (OSM v RT) in TMS, then it stands to reason that the same explanation could apply to NG vs GCM (and SDC:SC vs TRM). The OSM Legoiss/Tlead could use H2 fuel cells, but the RT Alpha/Beta are using PC in a Reflex Furnace.

The HG-blessed spec for the Alpha and all the other New Gen mecha indicates that they're powered by protoculture-based fuel cells... not a reflex furnace.

So, really, all that changed between the OSM and RT versions here is what the fuel cell electrolyte was.



ShadowLogan wrote:
~15L if each canister is about equal to a can of motor oil (as described, so it might be more/less), which means 32oz/1qt US (assuming the size hasn't changed over time/region).

Less, given that they have large contactor heads on either side, and if they're fuel cells they'll have channels for fuel and oxidizer, an anode, cathode, contactors, etc.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Thu Sep 12, 2019 12:04 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
You know as well as I do that this comic was written and published years before Harmony Gold's creative staff arrived at the decision to establish officially that the VF-1 used nuclear fusion instead of protoculture. That's the explanation for that line, not a new and exotic type of fusion power plant... nothing more or less than a retcon.

Technically they might not have rectoned anything, FTS in Chapter3 did have the prototype flying w/o the RF, suggesting the system could be a dual Fusion/Reflex-Furnace setup (the furance was required for G/B mode operation per Grant). It's also possible they flew the prototype with different engines for early stage testing (X-15 did just this). All it really indicates in the Infopedia is that they don't detail everything, which we know since no operating times or fuel loads are considered for omitted for example (and the RPG doesn't always get things right either).

Seto wrote:
The HG-blessed spec for the Alpha and all the other New Gen mecha indicates that they're powered by protoculture-based fuel cells... not a reflex furnace.

Maybe and then again Maybe Not.

Fuel Cells run off two materials, the Reflex Furnace diagram we see in "Bye Bye Mars" has 3 materials used for the Furnace that Lisa overloaded (green, yellow, blue lines to the purple furnace). We know one of those feed lines has to be Protoculture, what the other two lines are we don't know in a Reflex Furance. Given the NG designs, one could be an "oxidizer". The remaining one could simply be a coolant (which wouldn't need to be carried w/the cell) to take away excess heat or it could be involved in operation in another way (?).

Seto wrote:
Less, given that they have large contactor heads on either side, and if they're fuel cells they'll have channels for fuel and oxidizer, an anode, cathode, contactors, etc.

correction ~15L of material in the canisters then. However the size given isn't exact ("about the size of a can of motor oil") which gives a bit of wiggle room to add/subtract, but we also have to get the right size "can of motor oil". 1qt US might not be the proper size, we might be dealing with a canister closer to 5qt US (4.73L).

The Lineart (side profile view of cyclone) suggest a diameter of ~0.17m and no more than ~0.20m length, which works out to the canisters having no more than 4.5L of volume. This is based on ratio of canister diameter location to overall length in the art for the diameter (length is taken to be 2.05m per OSM dimension not the larger version RT uses). The length of the canister is the maxim width for that section (between front forks) of the cyclone I would estimate (this is using RT's stated width). The ratio for the dimensions is roughly what I work out from a perspective shot of a single loose canister, also in lineart. If these hold, then we are both way off in terms of total material per canister (72L total for the Alpha/Legoiss seems possible, but likely less for a variety of reasons for simplicity call it 64L total?).

Lineart:
http://www.gearsonline.net/series/mospe ... ada-07.gif
http://www.gearsonline.net/series/mospe ... hbt-02.gif


          Top  
 
Unread postPosted: Fri Sep 13, 2019 2:12 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
Technically they might not have rectoned anything, FTS in Chapter3 did have the prototype flying w/o the RF, suggesting the system could be a dual Fusion/Reflex-Furnace setup (the furance was required for G/B mode operation per Grant). It's also possible they flew the prototype with different engines for early stage testing (X-15 did just this). All it really indicates in the Infopedia is that they don't detail everything, which we know since no operating times or fuel loads are considered for omitted for example (and the RPG doesn't always get things right either).

Eh... that's a prototype, not a production aircraft. The Infopedia article is for the production aircraft, which was assumed (and semi-officially confirmed) to run on protoculture until the retcon that was to become the basis for RT2E's Macross Saga sourcebook's switch to fusion power for those mecha.

Granted, the Infopedia really doesn't detail much... but that's because the fan "experts" Harmony Gold outsourced the research to were painfully short on actual facts. Sometimes because those facts did not exist (e.g. Southern Cross), but equally as often because they just weren't aware that they existed in the first place.



ShadowLogan wrote:
Fuel Cells run off two materials, the Reflex Furnace diagram we see in "Bye Bye Mars" has 3 materials used for the Furnace that Lisa overloaded (green, yellow, blue lines to the purple furnace). We know one of those feed lines has to be Protoculture, what the other two lines are we don't know in a Reflex Furance. Given the NG designs, one could be an "oxidizer". The remaining one could simply be a coolant (which wouldn't need to be carried w/the cell) to take away excess heat or it could be involved in operation in another way (?).

... oooook? I'm not sure where you're trying to go with this, to be honest. Is it so surprising that an ersatz nuclear reactor would work differently than a fuel cell?

Mind you, it isn't even clear what the three substances being fed into the reaction chamber are in the original context of Super Dimension Fortress Macross. The labels on the diagram are in-jokes and while there are three substances that would normally be involved, only two should be coming from outside the reactor under normal circumstances. I'd expect an external coolant feed and fuel but the third substance, heavy quanta, would be generated by the fold carbon coil that's normally situated inside the reactor housing. (On VFs, there are usually only the two because the fuel slush and the intake air pull double duty as coolant and the fold carbon coil is inside the engine body.)

Protoculture in Robotech is essentially The Unexplainable, so trying to dig into it is fundamentally a waste of time for a macguffin that was NEVER given a coherent explanation in the show anyway (because it was an attempt to smash aspects of unrelated shows together).

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Fri Sep 13, 2019 3:24 pm
  

User avatar
Palladin

Joined: Wed Apr 15, 2009 8:33 pm
Posts: 10514
Location: Peterborough, Ontario
Comment: Yeah yeah yeah just give me my damn XP already :)
Unobtanium and Unexplainium. The basis of fiction forever. :lol:

_________________
I am very opinionated. Yes I rub people the wrong way but at the end of the day I just enjoy good hard discussion and will gladly walk away agreeing to not agree :D

Email - jlaflamme7521@hotmail.com, Facebook - Jaymz LaFlamme, Robotech.com - Icerzone

\m/


          Top  
 
Unread postPosted: Fri Sep 13, 2019 3:53 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
jaymz wrote:
Unobtanium and Unexplainium. The basis of fiction forever. :lol:

Yup, though the better sci-fi titles usually take the time to suss out how the advanced technology used in the story should work and set ground rules for what it can and can't do during development... so the stories produced are more consistent. It might require materials that are impossible with today's science or ways to exploit loopholes in physics that haven't been discovered yet in the real world but there's usually at least a coherent-ish explanation.

Unfortunately, because Robotech was conceived on the fly, the unique aspects of its technical setting doesn't have that background work behind them... so things like protoculture are inconsistent to the point where no coherent explanation exists.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Sat Sep 14, 2019 10:48 am
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Eh... that's a prototype, not a production aircraft. The Infopedia article is for the production aircraft, which was assumed (and semi-officially confirmed) to run on protoculture until the retcon that was to become the basis for RT2E's Macross Saga sourcebook's switch to fusion power for those mecha.

I agree its a prototype, and it could be using a different set of engines for early testing just like the real world X-15 used x2 XLR11 engines that powered the X-1 before it XLR99 engine was ready.

Still Grant's dialogue in Chapter 3 states that a Reflex Furance was necessary for G/B-mode operations. ("Sir, the prototype's been fully armed for live fire testing. However, the alternate configurations are not functional since we have not yet outfitted her with Dr. Langs's new reflex powerplants.") Then there is the scene in Chapter 4 with Roy testing the reflex furnace and the engineers talking in German, but it ends with mentioning they can restart testing of Battloid Mode. Nothing in FTS indicates if the engines used in Chapter 3 are temporary or used in conjunction with the RF so it could go any which way. Even the Ep5 dialogue line doesn't technically break anything given the actual definition of the RF in the RT-Glossary is that it is a reactor.

Seto wrote:
... oooook? I'm not sure where you're trying to go with this, to be honest. Is it so surprising that an ersatz nuclear reactor would work differently than a fuel cell?

At a basic level we could treat the OSM HBT fuel cell system as synonymous with OSM nuclear reactors from other sagas in Robotech sense they all use the same fuel source in Robotech. This means that while at the OSM level if we drilled down enough the Nuclear Engine in SDF:M will be different than GCM's HBT Fuel Cell, but at the Robotech level when we drill down they would be the same or more closely related.

IIRC there is even a scene in TRM where the dialogue if connected to the visual overlay might further add to this, but at the moment I can't find the scene in question, reinforcing the multi-line nature of a prototculture power plant.

A nuclear reactor at a deep level of detail operate differently than a fuel cell, but at a certain level of basic schematic they could be made to look the same. Not all Nuclear Fusion reactor designs use just Deuterium Hydrogen, some combine it with Helium-3 (not found on Earth, but out in space...) or Tritium Hydrogen Isotopes. The mixture types create even more energy than the pure Deuterium, but important here is that at a certain basic schematic level they might look like a fuel cell as you would have multiple feed lines.


          Top  
 
Unread postPosted: Mon Sep 16, 2019 1:58 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
Still Grant's dialogue in Chapter 3 states that a Reflex Furance was necessary for G/B-mode operations.

Which was true at the time the comic was written, back when the VF-1 was still assumed to use protoculture for its power source... but it hasn't been true for over a decade now, ever since the creative staff officially established that the Earth Forces mecha of the first two sagas use nuclear fusion power instead.



ShadowLogan wrote:
At a basic level we could treat the OSM HBT fuel cell system as synonymous with OSM nuclear reactors from other sagas in Robotech sense they all use the same fuel source in Robotech. This means that while at the OSM level if we drilled down enough the Nuclear Engine in SDF:M will be different than GCM's HBT Fuel Cell, but at the Robotech level when we drill down they would be the same or more closely related.

This is an assumption without any supporting evidence.



ShadowLogan wrote:
A nuclear reactor at a deep level of detail operate differently than a fuel cell, but at a certain level of basic schematic they could be made to look the same.

Only if you took it to the level of a black box diagram of "fuel in, power out".

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Tue Sep 17, 2019 1:17 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
This is an assumption without any supporting evidence.

The show dialogue identifies the Alpha power plant as a "protoculture generator" (ep83, Sue describes the shadow device) not a fuel cell or even a reactor for that matter. It could go either way based on the dialogue, but there are reasons to choose a "reactor" over a "fuel cell" interpretation w/n RT (pure Mospeada is another matter).

Changing the OSM Fuel Cells to a Reactor creates better technical continuity w/n the adaption (no need to justify the change from reactor based mecha to fuel cell based mecha in-universe for the VFs). A reactor makes more sense than a fuel cell for space capable mecha from a propulsion standpoint. Using a reactor based design allows for high thrust and efficiency, something you can't do with a fuel cell directly*.

HBT was replaced as the fuel source with Protoculture in Mospeada when it was adapted into Robotech. It isn't just a name change, as SLMH and Slush-H2 show there are deeper changes and those changes can impact operations. The OSM VF-1 went from a nuclear-esque system to a nuclear system (these and other known fusion engines can fit in the Alpha). OSM Mospedea ships don't have Fold Drives, but in RT they do now (SDF-4, Ikazuchi, Garfish), something similar probably applies to OSM SDC:SC ships to (I don't recall if the FTL system ever gets mentioned in dialogue). There are other examples of hardware changes beyond just a name change (Alpha's dedicated VTOL engines, Alpha head missiles, VHT main gun, Shadow Alpha gets a detachable cockpit ala VF-1, etc).

*There are no direct fuel-cell rockets AFAIK, electric rocket engines would require 10s of kw per Newton of thrust if not more (depending on type of engine). If we assume just the ATF-401 engines on the Legoiss/Alpha are for propulsion and the JG-97M are just for electrical power, they generate ~188kN of thrust total which means you would need ~1,883kW of electrical power with a 10kw/N of thrust ratio if I did the math right (and 10kw/N is being very overly generous).

Seto wrote:
Only if you took it to the level of a black box diagram of "fuel in, power out".

Maybe a bit higher, but that level of diagram is available in the show for the RF. I don't think we see anything at this level (or more detailed) for the NG mecha power plant (even when Sue describes the Shadow Device in Ep83) either, so w/n the show we don't have to go with the Fuel Cell approach in NG saga by depiction/dialogue. It isn't like RT is supposed to be a 100% adaption of the OSM supporting material (ignoring name changes).


          Top  
 
Unread postPosted: Wed Sep 18, 2019 12:44 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
The show dialogue identifies the Alpha power plant as a "protoculture generator" (ep83, Sue describes the shadow device) not a fuel cell or even a reactor for that matter. [...]

One of the biggest commercial applications of fuel cell technology is in large-scale backup generator systems used in things like corporate offices, hospitals, and large boats like cruise ships and freight haulers. Calling it a "protoculture generator" does not, in any way, shape, or form rule out it being a fuel cell system. It would, however, generally rule it out as a reactor system since reactors aren't generators, they power them (usually indirectly).



ShadowLogan wrote:
Changing the OSM Fuel Cells to a Reactor creates better technical continuity w/n the adaption [...]

No, it'd just create more plot holes when you're trying to establish something that directly contradicts the visuals. :roll:



ShadowLogan wrote:
A reactor makes more sense than a fuel cell for space capable mecha from a propulsion standpoint. Using a reactor based design allows for high thrust and efficiency, something you can't do with a fuel cell directly*.

The Alpha's not a space mecha... not really, anyway. That's a problem with the ill-conceived messes that was Shadow Chronicles, which wanted to reimagine the Alpha into a VF-1-esque design that it never was.



ShadowLogan wrote:
HBT was replaced as the fuel source with Protoculture in Mospeada when it was adapted into Robotech. It isn't just a name change, as SLMH and Slush-H2 show there are deeper changes and those changes can impact operations.

For one, SLMH doesn't exist in canon Robotech... it's only a thing in the RPG, which came up with it to have the fuel still be something exotic-sounding.

For two, the difference in performance isn't a result of a change in fuel... it's a result of a change in reactor technology. The OSM VF-1 uses a much more advanced, efficient, and powerful design that uses artificial gravity to catalyze and control the fusion reaction and contain the plasma stream. The Robotech VF-1 is using a conventional fusion reactor, presumably relying on a magnetic field pinch to compress the fuel and contain the plasma stream, which is much less efficient. You've got your cause and effect backwards.



ShadowLogan wrote:
The OSM VF-1 went from a nuclear-esque system to a nuclear system (these and other known fusion engines can fit in the Alpha).

But as they can't change the onscreen performance of the Alpha in the series, it's completely immaterial.



ShadowLogan wrote:
OSM Mospedea ships don't have Fold Drives, but in RT they do now (SDF-4, Ikazuchi, Garfish), [...]

This, on the other hand, was a 100% offscreen change... it didn't contradict anything in the animation, so they could get away with it easily.



ShadowLogan wrote:
something similar probably applies to OSM SDC:SC ships to (I don't recall if the FTL system ever gets mentioned in dialogue).

Ah, no... it doesn't. FTL travel wasn't exactly safe, but it was very definitely present in the OSM Southern Cross setting.

The invention of the warp drive - the Space Battleship Yamato kind, not the Star Trek kind - was what set up the entire plot. Earth's ecosystem was ruined by a nuclear holocaust, and the human race survived by emigrating into space and colonizing a habitable planet discovered in the Proxima Centauri system (Liberte) and later found and colonized a second inhabitable planet found in the Epsilon Eridani system (Glorie). The Zor were the descendants of the first wave of colonial pioneers sent to explore and terraform Glorie, who were catapulted into the distant past by a warp drive accident, colonized the planet, and were mutated into the Zor by exposure to the native protozor. One of the Southern Cross Army ships also weaponizes its warp drive at one point to destroy the Zor attack force assaulting it (RT calls this the "orbital warp blast"), and the support force from Liberte arrives in the Glorie system via warp drive.



ShadowLogan wrote:
There are other examples of hardware changes beyond just a name change (Alpha's dedicated VTOL engines, Alpha head missiles, VHT main gun, Shadow Alpha gets a detachable cockpit ala VF-1, etc).

Those first three are errors introduced by Robotech fans, which are nonsensical to anyone who looks into it even a little and even contradict the show in at least one case. The last one was part of HG's very deliberate attempt to Macross-ize the MOSPEADA setting for the "Shadow Saga" mentioned earlier.



ShadowLogan wrote:
*There are no direct fuel-cell rockets AFAIK, electric rocket engines would require 10s of kw per Newton of thrust if not more (depending on type of engine). If we assume just the ATF-401 engines on the Legoiss/Alpha are for propulsion and the JG-97M are just for electrical power, they generate ~188kN of thrust total which means you would need ~1,883kW of electrical power with a 10kw/N of thrust ratio if I did the math right (and 10kw/N is being very overly generous).

The turbines are the main propulsion system, the sub-engines are... sub-engines. They're a secondary propulsion system.

Let's stick to the facts, please, and not delve into fact-defying supposition.



ShadowLogan wrote:
Maybe a bit higher, but that level of diagram is available in the show for the RF. I don't think we see anything at this level (or more detailed) for the NG mecha power plant (even when Sue describes the Shadow Device in Ep83) either, so w/n the show we don't have to go with the Fuel Cell approach in NG saga by depiction/dialogue. It isn't like RT is supposed to be a 100% adaption of the OSM supporting material (ignoring name changes).

There's no pressing reason for it to NOT be fuel cells as in the original though. Robotech was not created to be a completely stand-alone story... it WAS an adaptation, and a rushed one at that.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Fri Sep 20, 2019 10:37 am
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
One of the biggest commercial applications of fuel cell technology is in large-scale backup generator systems used in things like corporate offices, hospitals, and large boats like cruise ships and freight haulers. Calling it a "protoculture generator" does not, in any way, shape, or form rule out it being a fuel cell system. It would, however, generally rule it out as a reactor system since reactors aren't generators, they power them (usually indirectly).

"Generator" though is not a slam dunk either way I do not dispute that, I am just saying that it would have been a good opportunity to call it something specific (ex: Fuel Cell, Reflex Furnace) in Robotech, but they went with something more generic. And there are nuclear "generators" in use:
-Radioisotope thermometric generator (form of nuclear energy, nearly every deep space probe uses them on missions past Mars orbit)
-Nuclear Fission Power Plants use the heat from the fission reaction to create steam to turn a turbine which powers a generator

Seto wrote:
For two, the difference in performance isn't a result of a change in fuel... it's a result of a change in reactor technology. (...)

The result in performance change is also a direct result of the fuel (for the RPG) if nothing else changes between the other OSM values (L of SLMH vs Slush-H2, thrust, consumption rate). Conventional Nuclear Fusion Propulsion systems (all theoretical) can achieve efficiencies better than the OSM-VF-1 (basically treat it as theoretical) by the math, which means it is possible for the RT-VF-1 to be on par or better than the OSM-VF-1 even if it is using a "conventional" setup.

Seto wrote:
But as they can't change the onscreen performance of the Alpha in the series, it's completely immaterial.

It doesn't require them to change the onscreen performance. Allow me to add for clarity: based on available fusion engine examples (VF-1, Logan, AGAC) it can be shown that they can produce examples sized to fit the Alpha and Beta, the thrust output of said fusion engines built for them doesn't change (screen performance shouldn't be impacted in this way) OR put those direct units in.

Seto wrote:
Ah, no... it doesn't. FTL travel wasn't exactly safe, but it was very definitely present in the OSM Southern Cross setting.

I know FTL exists in the setting, what I was saying was that I do not recall it being identified.

Seto wrote:
Those first three are errors introduced by Robotech fans, which are nonsensical to anyone who looks into it even a little and even contradict the show in at least one case. The last one was part of HG's very deliberate attempt to Macross-ize the MOSPEADA setting for the "Shadow Saga" mentioned earlier.


I am not saying I disagree or agree with you in the assessment of those changes from the OSM to RT, however those changes are RT "canon" until HG changes them. Which means that in RT terms they apply to the RT setting, but not the OSM setting. It also sets precedent that they can change things for Robotech purposes from what they are in the OSM beyond just a "name" change.

It might be nice if HG actually did a tech manual book bringing all 3 RT saga arcs into equal level of focus detail with more crunchy numbers/details than what is found in the Infopedia to avoid issues relating to what from the OSM actually applies and what doesn't. It also would mean they have the background detailed better for future projects (unlikely those maybe).

Seto wrote:
There's no pressing reason for it to NOT be fuel cells as in the original though. Robotech was not created to be a completely stand-alone story... it WAS an adaptation, and a rushed one at that.

As I said, I disagree. Moving the design from a Fuel Cell based setup in the OSM to a Reactor based setup in Robotech simplifies things.

It is a fact:
-the Alpha and Beta operate in space by some unknown propulsion means
-that Fuel Cells generate electricity
-that Fuel Cells are not viable for use as a direct propulsion means

Going the reactor route means we still have a source of electricity and characterize the propulsion system. Keeping the two separate means one still needs to work out what the propulsion system is AND explaining in-universe why the UEEF went with a split-souce setup instead of the single-source setup used by the UEDF: RDF and UEDF: ASC. UEEF designs in question seem to pre-date UEDF: ASC VFs.


          Top  
 
Unread postPosted: Fri Sep 20, 2019 2:07 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
"Generator" though is not a slam dunk either way I do not dispute that, I am just saying that it would have been a good opportunity to call it something specific (ex: Fuel Cell, Reflex Furnace) in Robotech, but they went with something more generic. And there are nuclear "generators" in use:
-Radioisotope thermometric generator (form of nuclear energy, nearly every deep space probe uses them on missions past Mars orbit)
-Nuclear Fission Power Plants use the heat from the fission reaction to create steam to turn a turbine which powers a generator

Point of order, neither of those is a "nuclear generator"... those are heat engines. At no point are they interacting directly with the nuclear fuel material or the alpha, beta, or gamma radiation that the radioisotope decay produces. There is no nuclear chain reaction occurring in the RTG's fuel, and in both cases they're harnessing the waste heat from the radioisotope decay via a fuel coolant medium as a heat source to generate electricity. Both technologies can (and are) readily deployed with non-nuclear fuels like coal, natural gas, hydrogen, etc.

A nuclear reactor doesn't produce electricity, it produces heat that is used to drive a generator.

A "nuclear generator" would be an alphavoltaic or betavoltaic nuclear battery that was directly capturing charged particles emitted by radioisotope decay to produce electrical power.



ShadowLogan wrote:
The result in performance change is also a direct result of the fuel (for the RPG) if nothing else changes between the other OSM values (L of SLMH vs Slush-H2, thrust, consumption rate).

... but other things DID change, like the fact that the reactor technology in the Robotech version is much more primitive, which makes its use of hydrogen as a fuel an EXTREMELY bad choice as the amount of energy you can harness from a single-stage hydrogen-hydrogen fusion reaction is fairly trivial.



ShadowLogan wrote:
[...] Conventional Nuclear Fusion Propulsion systems (all theoretical) can achieve efficiencies better than the OSM-VF-1 (basically treat it as theoretical) by the math, which means it is possible for the RT-VF-1 to be on par or better than the OSM-VF-1 even if it is using a "conventional" setup.

Yes, but that's a product of the limitations of modern fusion technology more than anything... they're maximizing the energy obtainable from a single-stage fusion reaction by using more energetic fuel in that single-stage reaction. They're not considering having to use the engines at high altitudes or in space, using them for large-scale energy generation, or in most cases even using the heat of the reaction as a source of propulsion energy. Most of the nuclear fusion propulsion studies for aviation are electrically-driven or mechanically-driven turbine concepts that use a central reactor inside the aircraft's fuselage.



ShadowLogan wrote:
I know FTL exists in the setting, what I was saying was that I do not recall it being identified.

"Orbital Warp Blast"... that bit in Robotech is lifted mostly directly from the original dialog, where the warping of space-time near a ship about to go FTL is a distinctly unhealthy place to be. It isn't quite the "get torn apart by a black hole and blasted into another dimension" of the Robotech version, but getting smashed to flinders by getting caught in the process of tying space in knots is not good for one's structural integrity.



ShadowLogan wrote:
I am not saying I disagree or agree with you in the assessment of those changes from the OSM to RT, however those changes are RT "canon" until HG changes them. Which means that in RT terms they apply to the RT setting, but not the OSM setting. It also sets precedent that they can change things for Robotech purposes from what they are in the OSM beyond just a "name" change.

The point I'm making here is that these "differences" are simply noteworthy inconsistencies created by Robotech fans who Did Not Do Research, and that while they are differences from the OSM spec they're mostly disprovable or obvious contradictions even within Robotech itself... they're not evidence of a deliberate creative choice to differ from the original shows.



ShadowLogan wrote:
It might be nice if HG actually did a tech manual book bringing all 3 RT saga arcs into equal level of focus detail with more crunchy numbers/details than what is found in the Infopedia to avoid issues relating to what from the OSM actually applies and what doesn't. It also would mean they have the background detailed better for future projects (unlikely those maybe).

That'd be fun... because five'll get you twenty the person they'd approach to write it would be ME. :lol:

I'm literally the only one doing full English translations of the tech manuals the original creators published. The only sensible way to approach a project like that would be to use it to finally rid the RT canon of the misinformation and errors introduced by the uRRG contributors.

The uRRG clown college has, mercifully, mostly dissolved and Harmony Gold now knows they're nowhere near as informed and authoritative as they pretended to be.



ShadowLogan wrote:
As I said, I disagree. Moving the design from a Fuel Cell based setup in the OSM to a Reactor based setup in Robotech simplifies things.

So far, I haven't seen any compelling reasoning to make such a dramatic change... especially one that would have knock-on effects WRT onscreen performance.



ShadowLogan wrote:
It is a fact:
-the Alpha and Beta operate in space by some unknown propulsion means
-that Fuel Cells generate electricity
-that Fuel Cells are not viable for use as a direct propulsion means

Entertainingly enough, we have several real world technology candidates for electrically-driven spacecraft propulsion like the ion thruster, microwave electrothermal thruster, and the plasma arcjet.

My preference, were I to call the shots, would be for the arcjet. The University of Stuttgart has done amazing work with hydrogen-powered MPD arcjets that've achieved exhaust velocities as high as 16km/s, and it'd be an easy sell for HG since MPD arcjets are used in the Macross franchise as missile propulsion systems.



ShadowLogan wrote:
Going the reactor route means we still have a source of electricity and characterize the propulsion system. Keeping the two separate means one still needs to work out what the propulsion system is AND explaining in-universe why the UEEF went with a split-souce setup instead of the single-source setup used by the UEDF: RDF and UEDF: ASC. UEEF designs in question seem to pre-date UEDF: ASC VFs.

That's fairly easy... you have an ultracompact power source and no need for propellant in atmospheric flight, meaning you can more readily reduce the size of an aircraft intended for use predominantly in atmospheric service when your propulsion system is an superconducting electrically-driven low-bypass turbofan jet engine and your space propulsion comes from an electric monopropellant rocket or ion thruster.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Sat Sep 21, 2019 4:28 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
... but other things DID change, like the fact that the reactor technology in the Robotech version is much more primitive, which makes its use of hydrogen as a fuel an EXTREMELY bad choice as the amount of energy you can harness from a single-stage hydrogen-hydrogen fusion reaction is fairly trivial.

You are right, I wanted to avoid the other changes the 2E RPG made because they just make the situation worse not better. By text implication and the math:
-exhaust velocity is greater than the speed of light (108.5% for the record)
-Delta-V is ~2,900kps

Seto wrote:
The point I'm making here is that these "differences" are simply noteworthy inconsistencies created by Robotech fans who Did Not Do Research, and that while they are differences from the OSM spec they're mostly disprovable or obvious contradictions even within Robotech itself... they're not evidence of a deliberate creative choice to differ from the original shows.

Not arguing, but the point is that HG has "agreed with" them making it "canon" (for however long before they change it). For discussion purposes participants have to be on the same page.

Seto wrote:
That'd be fun... because five'll get you twenty the person they'd approach to write it would be ME.

I am not thinking in terms of translation, I am thinking a ground up near-scratch build. Trying to mish-mash the OSM specs into something that makes sense seems like a lot more effort than simply doing a scratch build.

Seto wrote:
Entertainingly enough, we have several real world technology candidates for electrically-driven spacecraft propulsion like the ion thruster, microwave electrothermal thruster, and the plasma arcjet.

Yes I know we have the technology (and even used), but there are several drawbacks to it:
-1. Power Requirements are 10s of Kilowatts per Newtons of thrust (note Newton, not KiloNewton).*
-2. now you need to find more room to store propellant (or dedicate canisters)
-3. if you use fuel-cell by product for propellant, they will take a performance drop (those engine performance is calculated with specific propellant in mind, H2 is ideal but in some cases they do use other elements)
-4. a variety of limits exist on performance, while they leave Chemical Rockets in the dust (best is 500sec theoretical) they lose out to Fusion Systems in the long run (even a D-D hydrogen** system can achieve exhaust velocities that outclass the best electric rocket)

*I did the math a few posts up, but I'll repeat it here as I goofed up the units (feel free to check the math).
-Legoiss/Alpha ATF-401 engines are 4800kg of thrust (x4), total of 188,275.2N of thrust. With a Very Optimistic 10kilowatt per N of thrust, you'd need=1,882,752KW (or ~1,882.8MW). The JG-97 engines generate 1840sph each (3680sph total) or 2,706.6KW (or ~2.7MW). Obviously the Fuel Cells can not provide the electrical power to generate thrust (unless the FCs/PC is putting out over 100x more energy than the JG-97).
-VF-1's main engines create 11500kg of thrust (x2) w/o overboost, total of 225,538N of thrust and generate 650MW each (1,300MW total). Same optimistic KW/N requirement, you'd need 2,255.38MW. Even the VF-1 can not do this and not using overboost.

The 10KW/N is being very optimistic, even 1KW/N wouldn't work for the Legoiss/Alpha (it would for the VF-1).

**while "trivial" amounts of energy are released, there are numerous setups envisioned which each have their own efficiency zone. 100,000+sec is theoretically possible, even with D-D reaction (maybe not near term, but given RT could play the "leap frog" card due to alien technology involvement). Most serious fusion designs I find tend to focus more on the D-He3 fusion (RT could be doing this, and just being omitted it isn't like HG makes changes without full consideration).


          Top  
 
Unread postPosted: Sat Sep 21, 2019 8:42 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
You are right, I wanted to avoid the other changes the 2E RPG made because they just make the situation worse not better. By text implication and the math:
-exhaust velocity is greater than the speed of light (108.5% for the record)
-Delta-V is ~2,900kps

Honestly, with an odd statement like that I'd question the parameters you applied for your equation... it's probably not the safest or sanest idea to assume the 14 day endurance of the power plant is a maximum burn time for the engines in space as well. Kevin's not all that great with engineering and the hard sciences, so the RPG doesn't really take a realistic view of space operations. (Not that the show does either, but that's dramatic license being taken with respect to the physics of spaceflight.)



ShadowLogan wrote:
Seto wrote:
That'd be fun... because five'll get you twenty the person they'd approach to write it would be ME.

I am not thinking in terms of translation, I am thinking a ground up near-scratch build. Trying to mish-mash the OSM specs into something that makes sense seems like a lot more effort than simply doing a scratch build.

Eh... Harmony Gold doesn't ascribe to the view that Robotech should be something entirely separate from the shows it was adapted from. Given that the official specs are OSM-derived, or where they deviate the deviations were generally misrepresented as being OSM, it seems a VERY safe bet that Harmony Gold would want to draw as heavily on official Japanese source material as possible to write something like a technical manual. After all, there's bugger-all in the way of official Robotech info on how technology works but literally hundreds of pages on how the VF-1's systems work from the pens of designers like Shoji Kawamori and Masahiro Chiba. Even the artbook published by Udon is just a repackaging of existing materials like screen captures from the show, articles out of the Infopedia, and reprinted line art from Japanese artbooks.



ShadowLogan wrote:
Yes I know we have the technology (and even used), but there are several drawbacks to it: [...]

Granted, but we ARE talking about a science fiction setting where things like room temperature superconductors and fuels with greater energy density than uranium or plutonium are in casual use.


ShadowLogan wrote:
-VF-1's main engines create 11500kg of thrust (x2) w/o overboost, total of 225,538N of thrust and generate 650MW each (1,300MW total). Same optimistic KW/N requirement, you'd need 2,255.38MW. Even the VF-1 can not do this and not using overboost.

Yeah, but that assumes the VF-1's using an ion engine solo... they're doing something more along the lines of a hybrid fusion rocket similar to Star Trek's 23rd century impulse drives.

(Mind you, the original creators did actually account for this to a certain extent. The oldest version of the VF-1 spec actually has 650MW as typical/normal output in atmospheric service and 1,750MW per engine as the actual maximum output of the generators.)



ShadowLogan wrote:
**while "trivial" amounts of energy are released, there are numerous setups envisioned which each have their own efficiency zone. 100,000+sec is theoretically possible, even with D-D reaction (maybe not near term, but given RT could play the "leap frog" card due to alien technology involvement). Most serious fusion designs I find tend to focus more on the D-He3 fusion (RT could be doing this, and just being omitted it isn't like HG makes changes without full consideration).

In all likelihood, HG intended to copy Macross's approach but had insufficient information to actually do so... with Jason Marker filling in the gaps with an exotic fuel that wouldn't have actually been any help.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Sun Sep 22, 2019 12:19 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Honestly, with an odd statement like that I'd question the parameters you applied for your equation... it's probably not the safest or sanest idea to assume the 14 day endurance of the power plant is a maximum burn time for the engines in space as well. Kevin's not all that great with engineering and the hard sciences, so the RPG doesn't really take a realistic view of space operations. (Not that the show does either, but that's dramatic license being taken with respect to the physics of spaceflight.)

48hrs/2days not 14day for the VF-1 (the only VF we can do this with reliably, we don't have fuel capacity in kg or liters for the ASC mecha and we don't know the mass of a PC canister* to cover the A/B). The Alpha/Beta has 14days, the Logan/AGAC have 7days.

I know it is unlikely the VF-1 was to thrust at full for 48hrs, but the way the text reads such an interpretation is possible given the lack of qualifiers on just what "constant deployment" is supposed to entail. Even at 1/3 thrust output over 48hrs the VF-1 would have a huge operational range (one-way to the Moon in a couple of hours IINM, Mars depending on position in 2days, Pluto in a few weeks).

Granted this assumes the OSM thrust and fuel capacity values apply to the 2E RT RPG, given the mass of the unit is also different than the canon for the VF-1 (it isn't qualified as dry or full, so who knows what the author actually means) they may not.

*We can estimate it via a few ways (2.1kg per canister is the figure I came up with using the RPG PS and animation), or we can get an upper limit on the mass due to the fact full PC canisters float in water (we know the upper limit on volume, we know how dense water is). Granted the canisters might not be doing the floating (the carry handle might be, though the orientation they float is really weird).

Seto wrote:
Yeah, but that assumes the VF-1's using an ion engine solo... they're doing something more along the lines of a hybrid fusion rocket similar to Star Trek's 23rd century impulse drives.

I know that assumes the VF-1 is using an ion engine, it was to show how much electrical power would be needed if it did and why it would need to use something else. It shows that the power requirements are going to be immense, and at this point it would be easier and simpler to go with direct drive methods. While electrical drives have their appeal depending on mission parameters in the real world, they tend to lose out to fusion systems for main propulsion if they where available.

Seto wrote:
Granted, but we ARE talking about a science fiction setting where things like room temperature superconductors and fuels with greater energy density than uranium or plutonium are in casual use.

10kW per N was being generous, and could be seen as taking those factors into consideration (SC and ED materials) given the ratio is actually much higher (20:1 is the best I've seen). Some of the performance limitations aren't going to benefit from those factors so you might get the kW/N down, but you aren't going to necessarily get a performance improvement in other areas.

Seto wrote:
In all likelihood, HG intended to copy Macross's approach but had insufficient information to actually do so... with Jason Marker filling in the gaps with an exotic fuel that wouldn't have actually been any help.

I agree. Its almost like HG needs a science/technical advisor as part of their RT staff when writing for a what is supposed to be a Science Fiction show. It might also help if they fleshed out what they wanted before hand and stuck to it to avoid unnecessary rectons.


          Top  
 
Unread postPosted: Sun Sep 22, 2019 2:51 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
48hrs/2days not 14day for the VF-1 [...]

Ah, you're correct. I wonder where I latched onto 14 days?

That actually calls for a correction to my math for efficiency, since I'd used 14 days. The disparity is actually 14,583.333%, not 2,083.333%.



ShadowLogan wrote:
I know it is unlikely the VF-1 was to thrust at full for 48hrs, but the way the text reads such an interpretation is possible given the lack of qualifiers on just what "constant deployment" is supposed to entail. Even at 1/3 thrust output over 48hrs the VF-1 would have a huge operational range (one-way to the Moon in a couple of hours IINM, Mars depending on position in 2days, Pluto in a few weeks).

Palladium's system has no concessions made to the realistic concerns of space flight, so treating that maximum operating time as a space flight endurance is pretty silly on the face of it. Even though a good 2/3 of the Macross Saga is set in space, the RPG is written like everything happens in atmosphere. If the RT VF-1's engines work anything at all like the OSM VF-1's, its continuous operating time at full burn in space should be measured in minutes, not days. The OSM VF-1 burns its fuel 4,200x as fast in space as it does in atmosphere. Given that the mass of the SLMH in the RPG is 10x that of the slush hydrogen the OSM uses, I'd say the change in burn rate by mass should/would be 1/10th the OSM's... giving it 6 minutes and 51.43 seconds at maximum output before the tanks are empty. (This puts it at about 68.6% as efficient as the OSM VF-1 in space, all other non-relevant considerations being equal.) I'll sit down and work out how the various bolt-on tanks affect that later today.



ShadowLogan wrote:
Granted this assumes the OSM thrust and fuel capacity values apply to the 2E RT RPG, given the mass of the unit is also different than the canon for the VF-1 (it isn't qualified as dry or full, so who knows what the author actually means) they may not.

It's officially specified as a dry weight.



ShadowLogan wrote:
I know that assumes the VF-1 is using an ion engine, it was to show how much electrical power would be needed if it did and why it would need to use something else.

At real-world efficiencies... we don't have the luxury of things like room temperature superconductors and materials that can carry gigavolt loads without arcing all over hell's half-acre. The people in the OSM - and RT - do.



ShadowLogan wrote:
I agree. Its almost like HG needs a science/technical advisor as part of their RT staff when writing for a what is supposed to be a Science Fiction show. It might also help if they fleshed out what they wanted before hand and stuck to it to avoid unnecessary rectons.

Well, they were kind of stuck with what they had given that the original series was slapped together on the fly and in the greatest of haste. Despite Carl Macek's post-facto claims to the contrary, I do not think anyone involved in the production thought that the show was going to be anything more than a one-and-done toy commercial for an already not-terribly-successful Revell toy line. They were not expecting anyone to look at it as a serious work of science fiction, and expected their audience to be predominantly grade schoolers.

The original creators were writing for a much more mature audience of senior high schoolers and college students and had years to develop their content, so their work shows vastly more forethought and consistency... except in Southern Cross's case, where development was a train wreck conga line of course changes and knee-jerk decisions that is really quite baffling to read about.

(Really, how does a show go to production without even having a title decided-upon yet?)

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Sun Sep 22, 2019 5:17 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Ah, you're correct. I wonder where I latched onto 14 days?

Most likely in 2E it would have to come from the Alpha and Beta Fighters, they get 1/2 a month of constant use (full month of regular).

Seto wrote:
Palladium's system has no concessions made to the realistic concerns of space flight, (...)

I agree they model is more after atmospheric flight and you only get to this situation if you delve deeper than they intended.

Seto wrote:
Given that the mass of the SLMH in the RPG is 10x that of the slush hydrogen the OSM uses

Personally I keep the mass the same between SLMH and Slush-H2 as that keeps the changes made to just the volume for the fuel itself. Saves from having to do other adjustments, but also keeps in line with HG notion of sticking to the OSM as much as possible (as much as I dislike it, but by limited to volume I could justify it by the tanks being more armored/limited for an attempt at safety).

Seto wrote:
It's officially specified as a dry weight.

Unless it was changed from the Manga to the regular size (which I never picked up the 3core books in regular), the VF-1 (pg67m) is described as "Weight: 15 tons". In comparison the Alpha, Beta, AGAC, and Logan all list it as "Weight: [insert #] tons (dry)".

Seto wrote:
Well, they were kind of stuck with what they had given that the original series was slapped together on the fly and in the greatest of haste. Despite Carl Macek's post-facto claims to the contrary, I do not think anyone involved in the production thought that the show was going to be anything more than a one-and-done toy commercial for an already not-terribly-successful Revell toy line. They were not expecting anyone to look at it as a serious work of science fiction, and expected their audience to be predominantly grade schoolers.

I wasn't thinking about 85RT, I was thinking specifically about when they did the reset in 2001 and moving forward. Ex. Condor (go back far enough in RT.com in the Wayback Machine and you'll see it as the VF-5, then a nt-B to no reference), or the Beta's VF-# (go back to 2001 it was the VF-12, referencing the VF-5) or the VF-1's power plant (Reflex to Fusion, in 2001 the VF-1 couldn't go into orbit w/o a booster unit), etc.


          Top  
 
Unread postPosted: Mon Sep 23, 2019 2:53 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
I agree they model is more after atmospheric flight and you only get to this situation if you delve deeper than they intended.

Yeah, most players aren't going to look too deeply into the question of space flight endurance either since it never really comes up explicitly in the show.

AFAIK, the first time it actually came up in an animated feature was in the sixth episode of Macross Delta right before Hayate's first space sortie in episode six. Arad calls up a display of Hayate's VF-31 and its Super Pack with fuel tank level indicators and warns him to be careful of his fuel levels so he isn't left helpless in the middle of a dogfight due to lack of propellant. I don't recall it coming up in any of the novels except peripherally as a reason for equipping FAST Packs, and only one game even acknowledges the issue... Macross: Valkyrie Overdrive incorporated a fuel capacity limit on operating time for its space missions.

Normally they go for artistic license in depicting space combat no differently than aerial combat, so Palladium's approach could be called an acceptable break with reality for simplicity's sake. It's not like anyone besides us would pick nits on THAT level. :lol: For most, they never even question WHY the Alpha might not be capable of reaching suborbital trajectories or how the Beta would make it a possibility... it simply is.



ShadowLogan wrote:
Personally I keep the mass the same between SLMH and Slush-H2 as that keeps the changes made to just the volume for the fuel itself. Saves from having to do other adjustments, but also keeps in line with HG notion of sticking to the OSM as much as possible (as much as I dislike it, but by limited to volume I could justify it by the tanks being more armored/limited for an attempt at safety).

Given the inherently less efficient reactor technology in use, I'd have to stick with the OSM fuel tank capacity. If the engines work anything like they do in the OSM, reaction plasma is being used as the propellant in space, so cutting down the amount would cause even more problems given that the reactor's not operating at anywhere near the temperatures and pressures it is in the OSM so the plasma won't be as high-velocity as it would be and they'd need to expel more of it to achieve the same result.

Ironically, since the metallic hydrogen the RT version is using is at least metastable it should be easier to safely store than the cryogenic hydrogen slush the OSM VF-1 uses since it can be kept at STP.

Not having a cryogenic fuel might cause other issues though, since the VF-1 as outlined in the OSM uses the hydrogen slush that isn't being prepped for injection into the reaction chamber as coolant during space flight since it can't vent excess heat into atmospheric gases in a vacuum that doesn't have any.

(Come to that, there's another implicit advantage of the fuel cells the Alpha uses... you're not trying to cool a thermonuclear reactor.)



ShadowLogan wrote:
Unless it was changed from the Manga to the regular size (which I never picked up the 3core books in regular), the VF-1 (pg67m) is described as "Weight: 15 tons". In comparison the Alpha, Beta, AGAC, and Logan all list it as "Weight: [insert #] tons (dry)".

Huh, I forgot the RPG got the VF-1's weight wrong too... it should be 13,250kg, which the RT Infopedia rounded to 13.3t.



ShadowLogan wrote:
I wasn't thinking about 85RT, I was thinking specifically about when they did the reset in 2001 and moving forward. Ex. Condor (go back far enough in RT.com in the Wayback Machine and you'll see it as the VF-5, then a nt-B to no reference), or the Beta's VF-# (go back to 2001 it was the VF-12, referencing the VF-5) or the VF-1's power plant (Reflex to Fusion, in 2001 the VF-1 couldn't go into orbit w/o a booster unit), etc.

Part of that isn't really a science/technology issue as it is a Critical Research Failure. I mean, the Condor was never a transformable craft... so we see a fanfic classification get jettisoned and then toyed with before being abandoned as a bad job, some renumberings to ditch other fan assumptions like the Sylphid VF, removing something that was never actually in the show, and adding something which WAS in the show but had someone been overlooked. (We're responsible for that last one, at least.)

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Tue Sep 24, 2019 12:01 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Yeah, most players aren't going to look too deeply into the question of space flight endurance either since it never really comes up explicitly in the show.

Very true, however some of these numbers can still be useful for the GM and players. Which planets/moons can the VF in question launch into orbit? (we know Earth/Venus status, but what about others). The SLMH capacity (unlike PC canisters) is not easily quantifiable between various mecha (or put another way how to handle fuel transfer between X and Y, when X and Y are not the same).

Seto wrote:
AFAIK, the first time it actually came up in an animated feature was in the sixth episode of Macross Delta right before Hayate's first space sortie in episode six.

I can't speak for OSM-Macross, but RT-Macross had a fuel leak in Ep10 (Dixon's VF-1A) that scrubbed Vermillion flight (per regulation apparently given Fokker tells Hayes Hunter is correct in returning to base). There really isn't anything there for fuel to be used by directly (ie thrust, electricity), but it could indicate that the fuel is used as a coolant in that part of the mecha, but fuel loss/use is a concern in space flight when the plot demands.

Seto wrote:
Given the inherently less efficient reactor technology in use,

We know conventional fusion designs can match or exceed the rocket efficiency of the OSM-VF-1, so there doesn't appear to be a driving reason to reduce the efficiency in this respect. The technology might be more conventional going into the RT-reactors than the OSM-reactors, but it is possible for the relevant rocket performance values to stay the same (RT's reactors might have reduced net electrical power output).

Seto wrote:
Ironically, since the metallic hydrogen the RT version is using is at least metastable it should be easier to safely store than the cryogenic hydrogen slush the OSM VF-1 uses since it can be kept at STP.

I still think for safety keeping the mass the same instead of the volume is a valid point, after all if the contents are "activated" unintentionally do you want 119kg of SLMH going off or 1,190kg? The more there is the harder it will be to safely contain (or at least protect the pilot). Or put another way, when the H2 goes off the explosion needs to look the same (1,190kg of h2 going off makes a much bigger boom than 119kg) between the Slush and SLMH given the animation.

Another point is that the structure is intended to handle 119kg, and putting in 1,190kg in its place is going to add additional strain to various parts of the design (margin likely does exist). For example: can each of the wings/tanks actually handle 595kg of extra material, can the wing pivot mechanism? That extra 1,000kg or so will also impact acceleration. (since by the animation all these need to be identical).

Seto wrote:
(Come to that, there's another implicit advantage of the fuel cells the Alpha uses... you're not trying to cool a thermonuclear reactor.)

Except the thermonuclear reactor is going to generate thrust much more efficiently than the Fuel Cells.

You are not even avoiding the cooling per say, you've just moved the heat source from the separate generator to the propulsion unit itself (FYI some rocket engines do use propellant to cool the nozzle and combustion chamber).

Seto wrote:
Part of that isn't really a science/technology issue as it is a Critical Research Failure. I mean, the Condor was never a transformable craft... so we see a fanfic classification get jettisoned and then toyed with before being abandoned as a bad job, some renumberings to ditch other fan assumptions like the Sylphid VF, removing something that was never actually in the show, and adding something which WAS in the show but had someone been overlooked. (We're responsible for that last one, at least.)

I agree these examples are not science/technical advisor level, but apply to the other part of my statement concerning "fleshed out what they wanted before hand and stuck to it to avoid unnecessary rectons."

Actually the Beta being the -12 would make sense if the AGAC is the -10, since the revised Beta received a new number that post dates the AGAC (by all indications). IINM though even the uRRG didn't suggest the VF-7 Slyphid until 2003 on their site formally (internally no idea how long it was floating around). While the Condor wasn't transformable in the OSM, given its depiction and resemblance to the Beta/Alpha in places one might get it to transform (might not look pretty though) which RT might be able to do (assuming they don't mind creating differences between the OSM and RT). Then again nothing exists in RT (at the time) that requires the Condor to be treated as a VF, it could be treated as a VHT (w/space augmentation pack options), an nt-B, or even an early Alpha w/add-ons.


          Top  
 
Unread postPosted: Tue Sep 24, 2019 1:24 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
Very true, however some of these numbers can still be useful for the GM and players. Which planets/moons can the VF in question launch into orbit? (we know Earth/Venus status, but what about others).

Since every alien planet/moon to actually appear in canon Robotech thus far has adhered to that old sci-fi trope that all alien planets are Earthlike to the extent that the atmospheric composition and local gravity fail to pose even trivial obstacles to humans operating there without any protective equipment at all, the question would appear to be largely academic for Robotech. Less so for those of us using the RPG to run Macross games since the New UN Government there isn't shy about building space colonies and surface installations on uninhabitable and even downright hostile balls of rock like Luna, Venus, Mars, Ceres, Europa, Ganymede, and the ring systems of Jupiter and Saturn.



ShadowLogan wrote:
The SLMH capacity (unlike PC canisters) is not easily quantifiable between various mecha (or put another way how to handle fuel transfer between X and Y, when X and Y are not the same).

Yeah, that's definitely one of those fiddly details that falls into the domain of "GM's discretion".



ShadowLogan wrote:
I can't speak for OSM-Macross, but RT-Macross had a fuel leak in Ep10 (Dixon's VF-1A) that scrubbed Vermillion flight (per regulation apparently given Fokker tells Hayes Hunter is correct in returning to base). There really isn't anything there for fuel to be used by directly (ie thrust, electricity), but it could indicate that the fuel is used as a coolant in that part of the mecha, but fuel loss/use is a concern in space flight when the plot demands.

They never do identify what he's leaking in the OSM, but given he got hit in the front landing gear bay it's probably hydraulic fluid. There should be fuel lines in there to feed the verniers in the nose at least, but they shouldn't be capable of leaking THAT much fuel.



ShadowLogan wrote:
Seto wrote:
Given the inherently less efficient reactor technology in use,

We know conventional fusion designs can match or exceed the rocket efficiency of the OSM-VF-1, so there doesn't appear to be a driving reason to reduce the efficiency in this respect. The technology might be more conventional going into the RT-reactors than the OSM-reactors, but it is possible for the relevant rocket performance values to stay the same (RT's reactors might have reduced net electrical power output).

Eh... only if we ignore the question of scale... but remember the RT version is burning fuel at 1,458x the rate of the OSM version, all other relevant concerns being equal.



ShadowLogan wrote:
I still think for safety keeping the mass the same instead of the volume is a valid point, after all if the contents are "activated" unintentionally do you want 119kg of SLMH going off or 1,190kg? The more there is the harder it will be to safely contain (or at least protect the pilot). Or put another way, when the H2 goes off the explosion needs to look the same (1,190kg of h2 going off makes a much bigger boom than 119kg) between the Slush and SLMH given the animation.

My question would be how you're going to achieve any kind of explosion from a tank full of hydrogen without any kind of oxidizer present. Yeah, the OSM VF-1's tanks are under pressure but the ones housing the RT one's more reactive fuel aren't... and neither is going to burn explosively, or indeed at all, in the absence of oxygen.



ShadowLogan wrote:
Another point is that the structure is intended to handle 119kg, and putting in 1,190kg in its place is going to add additional strain to various parts of the design (margin likely does exist). For example: can each of the wings/tanks actually handle 595kg of extra material, can the wing pivot mechanism? That extra 1,000kg or so will also impact acceleration. (since by the animation all these need to be identical).

Given the stated structural strengths of the materials? Yes, an extra thousand kilograms should pose no structural issues whatsoever. The VF-1's airframe is stressed to take off and fly with an extra 24,000kg on top of that. That difference is literally less than the mass of a loaded gunpod and well under the weight limit of any of the aircraft's four pylons (never mind all four together).



ShadowLogan wrote:
Except the thermonuclear reactor is going to generate thrust much more efficiently than the Fuel Cells.

Perhaps, but it's going to be a lot less compact than fuel cells and running a lot hotter.



ShadowLogan wrote:
I agree these examples are not science/technical advisor level, but apply to the other part of my statement concerning "fleshed out what they wanted before hand and stuck to it to avoid unnecessary rectons."

... yeah, but if planning ahead were part of the Robotech experience, Robotech wouldn't exist at all.



ShadowLogan wrote:
Actually the Beta being the -12 would make sense if the AGAC is the -10, since the revised Beta received a new number that post dates the AGAC (by all indications). IINM though even the uRRG didn't suggest the VF-7 Slyphid until 2003 on their site formally (internally no idea how long it was floating around). While the Condor wasn't transformable in the OSM, given its depiction and resemblance to the Beta/Alpha in places one might get it to transform (might not look pretty though) which RT might be able to do (assuming they don't mind creating differences between the OSM and RT). Then again nothing exists in RT (at the time) that requires the Condor to be treated as a VF, it could be treated as a VHT (w/space augmentation pack options), an nt-B, or even an early Alpha w/add-ons.

*shrug* Blame Sentinels for screwing the pooch there.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Wed Sep 25, 2019 12:01 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Since every alien planet/moon to actually appear in canon Robotech thus far has adhered to that old sci-fi trope that all alien planets are Earthlike to the extent that the atmospheric composition and local gravity fail to pose even trivial obstacles to humans operating there without any protective equipment at all, the question would appear to be largely academic for Robotech.

Mars and Luna do appear in cannon and they certainly don't have Earth like gravity (facilities might use ArG), so we know some extra-terrestial worlds are utilized by Terrans even in the 2040s that's don't fit that mold. Obviously these non-Earth like worlds will need some reason to be there (research, mining, etc), but we know it's atleast possible the UEEF looks at non-Earth-like worlds for use.

Seto wrote:
Eh... only if we ignore the question of scale... but remember the RT version is burning fuel at 1,458x the rate of the OSM version, all other relevant concerns being equal.

RT's fusion systems, conventional they maybe, might also get a boost from the SDF-1 reverse engineering. This means they could in theory get some miniturization technology from the SDF-1.

The Fuel Burn Rate though assumes a 1:1 Volume exchange, if the Fuel is exchanged 1:1 for mass they would be the same.

EDIT:
While I am all for RT differentiating from the OSM, a 1:1 mass exchange is the simplest to execute without more input from HG on what else changed from the OSM.

Given the OSM VF-1 and RT VF-1 share animation (Ep1-36), that means performance statistics should be the same or else some values have to be recalculated for RT due to using partial OSM numbers. Adding ~1,078kg of material means that in order for the RT VF-1 and OSM VF-1 to have identical T/W ratios (ie acceleration), the RT VF-1A/J/D would now need ~6% more thrust (~6.3% if using HG's rounded dry mass). It could impact the Delta-V and Specific Impulse, or the Isp could remain the same with a higher mass flow rate to achieve ~6% increase. At this point I don't think we can know what those changes actually look like between RT and the OSM as there are several ways to achieve a 6% increase with no correct solution, and each solution's impact differs to. Which leads to the simplest change (1:1 mass) as it has a much smaller impact.

Seto wrote:
My question would be how you're going to achieve any kind of explosion from a tank full of hydrogen without any kind of oxidizer present. Yeah, the OSM VF-1's tanks are under pressure but the ones housing the RT one's more reactive fuel aren't... and neither is going to burn explosively, or indeed at all, in the absence of oxygen.

If battle damage disrupts the SLMH stability then it could revert to a less dense stage expanding in volume and rupturing the tank (ie "explosion"). In an atmosphere environment a fuel leak could provide oxidizer at the site of the leak.

Seto wrote:
The VF-1's airframe is stressed to take off and fly with an extra 24,000kg on top of that.

While I do not doubt the OVERALL airframe is rated for an extra 24 metric tons given the FAST Pack/GBP systems, the wings (H2 tank location correct) THEMSELVES may not be intended to handle part of that 24metric tons. Look at what sections of the airframe receive the add-ons: fuselage, arms, and the legs. Wings? None (AFAIK), suggesting the pivot mechansim and/or sub-structure itself might not have room to handle the extra mass (at least in a fully loaded configuration, obviously you can balance out fuel load and weapons to make it work).

Seto wrote:
Perhaps, but it's going to be a lot less compact than fuel cells and running a lot hotter.

Hotter, likely (at least fusion to H2 fuel cell, a PC "fuel-cell" with its higher energy density who knows). More compact? That seems less likely, at least in terms of size/output.


          Top  
 
Unread postPosted: Fri Oct 11, 2019 12:44 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
Sorry for the delay in replying, I was on holiday and for some reason my VPN and the forums don't get along.

ShadowLogan wrote:
Mars and Luna do appear in cannon and they certainly don't have Earth like gravity (facilities might use ArG), so we know some extra-terrestial worlds are utilized by Terrans even in the 2040s that's don't fit that mold. Obviously these non-Earth like worlds will need some reason to be there (research, mining, etc), but we know it's atleast possible the UEEF looks at non-Earth-like worlds for use.

Those aren't exactly alien... they're right in our solar system, and both have negligible to nonexistent atmospheres and minimal surface gravity. Every alien planet or moon visited by the UEEF in canon seems to have a human-breathable atmosphere and 1g mean surface gravity, which would also tend to make the question of performance on planets that aren't Earthlike a nonissue (by dint of actually never visiting any).


ShadowLogan wrote:
RT's fusion systems, conventional they maybe, might also get a boost from the SDF-1 reverse engineering. This means they could in theory get some miniturization technology from the SDF-1.

The Fuel Burn Rate though assumes a 1:1 Volume exchange, if the Fuel is exchanged 1:1 for mass they would be the same.

One of our foundational assumptions here is that the actual structural design of the fighter didn't change... which would make the by-volume exchange the more logical of the two.


ShadowLogan wrote:
While I am all for RT differentiating from the OSM, a 1:1 mass exchange is the simplest to execute without more input from HG on what else changed from the OSM.

Fuel tanks are, as a rule, generally measured by fluid volume... not fuel mass. The fluid volume is what's listed in the OSM spec.


ShadowLogan wrote:
Given the OSM VF-1 and RT VF-1 share animation (Ep1-36), that means performance statistics should be the same or else some values have to be recalculated for RT due to using partial OSM numbers. Adding ~1,078kg of material means that in order for the RT VF-1 and OSM VF-1 to have identical T/W ratios (ie acceleration), the RT VF-1A/J/D would now need ~6% more thrust (~6.3% if using HG's rounded dry mass).

The empty thrust-to-weight ratio wouldn't be impacted, only the loaded one... this is an area where the Robotech spec is too vague to draw conclusions since it doesn't offer anything apart from the empty weight. 1,078kg is a fairly trivial amount of additional weight even for the OSM spec, and would not have a meaningful impact on performance. This would only really become an issue for what's depicted onscreen if we had a clear-cut case of a VF-1 operating at the absolute maximum possible performance, and we don't have any instances of that.


ShadowLogan wrote:
If battle damage disrupts the SLMH stability then it could revert to a less dense stage expanding in volume and rupturing the tank (ie "explosion"). In an atmosphere environment a fuel leak could provide oxidizer at the site of the leak.

That wouldn't really get you an explosion... if you've got a rupture in the tank through which that now higher-pressure fluid is escaping, you've got a rocket not a bomb. Rather like shooting a hole in a propane tank (thanks MythBusters).


ShadowLogan wrote:
While I do not doubt the OVERALL airframe is rated for an extra 24 metric tons given the FAST Pack/GBP systems, the wings (H2 tank location correct) THEMSELVES may not be intended to handle part of that 24metric tons. Look at what sections of the airframe receive the add-ons: fuselage, arms, and the legs. Wings? None (AFAIK), suggesting the pivot mechansim and/or sub-structure itself might not have room to handle the extra mass (at least in a fully loaded configuration, obviously you can balance out fuel load and weapons to make it work).

Much of the fuel is actually stored in the legs, because the cryogenic fuel was used as a coolant for the engines in space operations. The CTF-04 conformal tanks for the FAST Packs essentially connect directly to the main tanks. There's a pretty significant safety margin for the wings even in the earliest versions of the spec, with their payload capacity being several thousand kilograms more than any payload configuration they pylons could support, to the extent that some of the later materials have depicted a second set of 120,000kgf rocket boosters being bolted directly to the wings. If the wing can handle THAT, the additional stress of a few hundred kg of fuel slush should be a nonissue.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Sat Oct 12, 2019 11:32 am
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Those aren't exactly alien... they're right in our solar system, and both have negligible to nonexistent atmospheres and minimal surface gravity. Every alien planet or moon visited by the UEEF in canon seems to have a human-breathable atmosphere and 1g mean surface gravity, which would also tend to make the question of performance on planets that aren't Earthlike a nonissue (by dint of actually never visiting any).

To a point I agree, however the main point is that the fact that the Moon and Mars are home to UEEF installations, which means it is possible that outside the Solar System the UEEF could find its way to similar worlds for its installations.

Seto wrote:
One of our foundational assumptions here is that the actual structural design of the fighter didn't change... which would make the by-volume exchange the more logical of the two.

There are 3 ways this issue resolves itself. So in no particular order:
1. keep the volume 1:1 and deal with cascade changes to various performance metrics
2. keep the volume 1:1 and increase the burn-time to balance things out, this will cause a change in Delta-V (greater) but otherwise be identical otherwise to the OSM for performance.
3. do a 1:1 mass exchange, which keeps other performance based values the same. The only other change is to alter the capacity of the fuel tanks.

#1 and #2 have secondary issues associated with them. You now have the more massive RT VF-1 moving identically to the lighter OSM VF-1 in the animation, which requires other changes to balance things out. That extra thrust then throws off other values since we don't know what else changes because of them. By the math we have several options to consider then if the thrust in RT has to be more, but none of them come in as "this is the one" to explain it away (does it simply increase the mass/flow rate, or alter the exhaust velocity, some combination of the two? and why that choice instead of the others).

Really the simplest and most logical would be to do #3 as it doesn't require any performance changes and keeps changes to a minimum. You might even justify keep the same external size of the tanks, just alter their internal capacity (and add safety features).

Seto wrote:
That wouldn't really get you an explosion... if you've got a rupture in the tank through which that now higher-pressure fluid is escaping, you've got a rocket not a bomb. Rather like shooting a hole in a propane tank (thanks MythBusters).

I'm not sure if the propane tank hole is a good example to base a conclusion on. You aren't going to set off the propane in a tank by making a hole in it (nor shooting a gas tank).

SLMH can basically function as a monopropellant, which leads me to think you have to worry about the stuff becoming destabilized in the tanks (causing a build up of pressure and release of energy).


          Top  
 
Unread postPosted: Wed Oct 23, 2019 12:57 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
ShadowLogan wrote:
To a point I agree, however the main point is that the fact that the Moon and Mars are home to UEEF installations, which means it is possible that outside the Solar System the UEEF could find its way to similar worlds for its installations.

Granted, but if there's no need to set up shop on an inhospitable rock, why would they? The main reason the UEEF has major installations on Luna and Mars is because the UEDF screwed up and lost Earth to an occupying alien force. It's easier by far for them to set up shop on habitable planets controlled by their allies like they did on Tirol. Their enemies, the Invid, also don't seem interested in inhospitable rockballs like Luna since the Flowers of Life can't grow there (and in the Regent's case, there's nobody to oppress and murder like the cackling saturday morning cartoon villain he is.)



ShadowLogan wrote:
There are 3 ways this issue resolves itself. So in no particular order:
1. keep the volume 1:1 and deal with cascade changes to various performance metrics
2. keep the volume 1:1 and increase the burn-time to balance things out, this will cause a change in Delta-V (greater) but otherwise be identical otherwise to the OSM for performance.
3. do a 1:1 mass exchange, which keeps other performance based values the same. The only other change is to alter the capacity of the fuel tanks.

The underlying problem with 1 and 2 is that you're assuming that the small amount of extra mass is outside the acceptable loading bounds of the VF-1's design to the extent that it'd produce significant differences in performance. From the OSM spec, that additional mass is still well within normal operational loading spec for the VF-1.



ShadowLogan wrote:
I'm not sure if the propane tank hole is a good example to base a conclusion on. You aren't going to set off the propane in a tank by making a hole in it (nor shooting a gas tank).

You're not going to set off stable metallic hydrogen that way either, so it's a good parallel... if a modest shock or tank rupture is sufficient to cause the hydrogen to revert from its metallic state, then it wasn't stable to begin with. You're not wrong that it could be a monopropellant... if it wasn't stable.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Wed Oct 23, 2019 6:20 pm
  

User avatar
D-Bee

Joined: Sun Jun 02, 2019 6:40 am
Posts: 36
Seto Kaiba wrote:
ShadowLogan wrote:
To a point I agree, however the main point is that the fact that the Moon and Mars are home to UEEF installations, which means it is possible that outside the Solar System the UEEF could find its way to similar worlds for its installations.

Granted, but if there's no need to set up shop on an inhospitable rock, why would they? The main reason the UEEF has major installations on Luna and Mars is because the UEDF screwed up and lost Earth to an occupying alien force. It's easier by far for them to set up shop on habitable planets controlled by their allies like they did on Tirol. Their enemies, the Invid, also don't seem interested in inhospitable rockballs like Luna since the Flowers of Life can't grow there (and in the Regent's case, there's nobody to oppress and murder like the cackling saturday morning cartoon villain he is.)


Some experiences with highly energetic prototypes could be better suited on a dead world which would be no great loss to environmental damage. Such was the case of the Reflex furnaces on mars, for one. There is also the fact that it might be more likely to successfully hide a secret project on such a uninteresting world. Using the ground itself as shelter from bombardments and other active / passive sensors. A refuelling station near enemy lines could prove useful without needing the full atmosphere / gravity and other requirements for permanent settlements. New Gen certainly still have traces of the idea of the Solar System being used in this way. I don't see why this philosophy would turn out different results for the UEEF in alien systems.
And... If you adhere to the idea that there might be still some form of capitalistic / legal frame to the civilian sector of RT, then you might be able to avoid some legal frame by going to these remote places. (Though that particular idea is not very well explored outside of old secondary canon material.)

Likewise, Invid scientists have been known to go to remote places for their genesis pit experiments. Since these can be globally controlled environments, even counting on artificial sky lighting, I'd wager the atmosphere and gravity requirements would not be a problem once inside. Which doesn't mean the UEEF won't have to go through these exotic places to get in. Conversely, the ones on earth had a primitive humidity and oxygen level, which could mean even more varied settings for the off-world pits.

It's true however that the books themselves do not give us many rules or hints that such scenario should be considered realistically. Or maybe the idea is that it is no longer a problem for the technology.
If they did, if it was still a problem, even just the solar system would present all kinds of challenge for such plane-like objects.
See : Interplanetary Cessna

_________________
On the wrong forum, 30 years too late...


          Top  
 
Unread postPosted: Thu Oct 24, 2019 12:08 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
Granted, but if there's no need to set up shop on an inhospitable rock, why would they? The main reason the UEEF has major installations on Luna and Mars is because the UEDF screwed up and lost Earth to an occupying alien force. It's easier by far for them to set up shop on habitable planets controlled by their allies like they did on Tirol. Their enemies, the Invid, also don't seem interested in inhospitable rockballs like Luna since the Flowers of Life can't grow there (and in the Regent's case, there's nobody to oppress and murder like the cackling saturday morning cartoon villain he is.)

While I agree it would be much easier to setup on a habitable world, the vast majority of worlds the UEEF is going to encounter are going to be uninhabitable (less than 1% of the planet/moon/dwarf worlds in our solar system are habitable if that's anything to go on). Their use to the UEEF isn't going to go away just because they aren't "habitable", they still come with vast resources and locations that could be useful to the UEEF.

There is also that pesky comment in NG#1 about being "born out in deep space aboard a robotech ship" (not intended as exact quote), and Scott's "it's as vast as Venus" (not intended as exact quote, though weather he is talking about Solar System Venus or another geographic loaction isn't known). There is also the part in AotSC (pg36) about ALUCE Base being involved in Lunar Colonization (pre-2RW). Suggesting that Terrans weren't being too particular about worlds they intended to colonize.

Seto wrote:
The underlying problem with 1 and 2 is that you're assuming that the small amount of extra mass is outside the acceptable loading bounds of the VF-1's design to the extent that it'd produce significant differences in performance. From the OSM spec, that additional mass is still well within normal operational loading spec for the VF-1.

The loading limits of the VF-1 aren't strictly the only factor to consider though. The two mecha (OSM & RT version) are supposed to have identical acceleration going off the animation, which means in order for that to be true the Thrust generated has to be more on the RT version, which means even more performance numbers change. Actuator ratings for limb movement also need to go up (or cut into any margin they have). The catapults on the carriers have to be re-calibrated (heavier craft), the various Booster units also need re calibration (heavier craft). Really the simplest option is #3 as it doesn't have as far reaching consequences (or option #4 HG goes back to the OSM's Slush-H2)

Force = Mass * Acceleration
1N = 1kg * 1m/s/s (Osm)
1.08N = 1.08kg *1m/s/s (RT)

Limiting the tankage might also be appropriate from a cost perspective (how expensive is it for Earth to manufacture SLMH), especially in the early years when the necessary infrastructure might not be present. This would necessitate a balancing act between various production requirements (SLMH and the platforms that use it). Its also possible that the tanks are as large, but standard operations only fill it by 1/10th of volume (in RT, though the same mass as the OSM) due to overall supply of the fuel and/or no operational need to fill the tanks to full.

Seto wrote:
You're not going to set off stable metallic hydrogen that way either, so it's a good parallel... if a modest shock or tank rupture is sufficient to cause the hydrogen to revert from its metallic state, then it wasn't stable to begin with. You're not wrong that it could be a monopropellant... if it wasn't stable.

A rupture by a solid projectile may not apply 1:1 for an energy beam weapon, which is why I think the propane (or even just gasoline) is a bad example to base things on. They have to destabilize the SLMH to be useful in the engine/reactors, and some fusion research involves using lasers (energy beam weapon) to initiate fusion. This leads me to think some degree of over engineering for safety is going to happen, at least until humans get more operational experience with the stuff.


          Top  
 
Unread postPosted: Thu Oct 24, 2019 1:09 pm
  

User avatar
Knight

Joined: Tue Dec 14, 2010 6:36 am
Posts: 5021
Location: New Frontier Shipyard, Earth-Moon L5
Comment: "My theories appall you, my heresies outrage you, I never answer letters, and you don't like my tie."
xunk16 wrote:
Some experiences with highly energetic prototypes could be better suited on a dead world which would be no great loss to environmental damage. Such was the case of the Reflex furnaces on mars, for one.

The UEEF didn't have anything like that going on... barring the one live-fire test of a neutron-s warhead in 2044, which was absolutely a Haydonite trap. (The UEEF didn't build those warheads, so they didn't actually know what they did... which was the entire reason the test was conducted.)


xunk16 wrote:
There is also the fact that it might be more likely to successfully hide a secret project on such a uninteresting world. Using the ground itself as shelter from bombardments and other active / passive sensors.

... but the UEEF didn't have anything like THAT going on either. Never mind that those kind of protective measures would've offered no protection at all against detection by the Invid.

What little R&D the UEEF was doing was explicitly undertaken at Space Station Liberty and the UEEF compound in Tiresia.

Their enemy didn't have any espionage capability to speak of, so that kind of secrecy would be completely pointless.


xunk16 wrote:
A refuelling station near enemy lines could prove useful without needing the full atmosphere / gavity and other requirements for permanent settlements.

The entire concept of "enemy lines" doesn't really apply to the foe the UEEF was fighting... the Invid were purely a planetary occupation force. They didn't have a combat-effective space force of any size... the best they could do for space defense was running their regular ground troops up into orbit on defenseless short-range spacecraft for suicidal zerg rushes.


xunk16 wrote:
New Gen certainly still have traces of the idea of the Solar System being used in this way.

No, it doesn't. Mars Base's actual military purpose is never elaborated upon and ALuCE Base on Luna wasn't a refueling depot it was a mining complex-turned-staging area for the UEEF to muster their troops for invasions of Earth.


xunk16 wrote:
And... If you adhere to the idea that there might be still some form of capitalistic / legal frame to the civilian sector of RT, then you might be able to avoid some legal frame by going to these remote places. (Though that particular idea is not very well explored outside of old secondary canon material.)

Minmei was literally the ONLY adult human civilian with the UEEF in pretty much every version of Sentinels. Even the RPG is pretty clear that there wasn't a civilian presence, explicitly stating that the military was the ONLY career path for people born or living in space.


xunk16 wrote:
Likewise, Invid scientists have been known to go to remote places for their genesis pit experiments.

Not in the official setting.


xunk16 wrote:
If they did, if it was still a problem, even just the solar system would present all kinds of challenge for such plane-like objects.
See : Interplanetary Cessna

... not really, the particular problems elaborated upon in that xkcd comic are confined to engines that are only capable of operating in atmosphere. They don't really apply to any of the space-capable aircraft in Robotech or Macross, which either have separate engines for use in vacuum or dual-mode engines that can run as turbines in atmosphere and augmented fusion rockets in space.








ShadowLogan wrote:
While I agree it would be much easier to setup on a habitable world, the vast majority of worlds the UEEF is going to encounter are going to be uninhabitable (less than 1% of the planet/moon/dwarf worlds in our solar system are habitable if that's anything to go on). Their use to the UEEF isn't going to go away just because they aren't "habitable", they still come with vast resources and locations that could be useful to the UEEF.

On that, I am not so sure... surface-based mining operations aren't really necessary when you can just tow asteroids back to your space station and mine them in relative comfort and safety. All the benefits, none of the drawbacks. The UEEF's operations were pretty much exclusively on habitable planets in Sentinels. Optera's the closest they're ever shown to visiting an uninhabitable world outside our own solar system, and even that's still capable of supporting human life with no protective gear whatsoever... it just suffered a total ecological collapse thanks to the bombardment of the planet's surface.


ShadowLogan wrote:
There is also that pesky comment in NG#1 about being "born out in deep space aboard a robotech ship" (not intended as exact quote), and Scott's "it's as vast as Venus" (not intended as exact quote, though weather he is talking about Solar System Venus or another geographic loaction isn't known). There is also the part in AotSC (pg36) about ALUCE Base being involved in Lunar Colonization (pre-2RW). Suggesting that Terrans weren't being too particular about worlds they intended to colonize.

Whether he's talking about anything at all when he says "as vast as Venus" is debatable... there isn't any base on Venus, and he's never been to the planet. He's just channeling Burt Ward. :wink:

ALuCE base is a slightly different concern, but it was set up as the closest possible resource station to a devastated Earth. Humanity's willing to set up bases on inhospitable worlds, but only if there's absolutely no other choice... and since all the worlds they're operating on in the course of the UEEF's mission are Earthlike they're doing things on Star Trek-level Extraterrestrial Easy Mode.


ShadowLogan wrote:
The loading limits of the VF-1 aren't strictly the only factor to consider though. The two mecha (OSM & RT version) are supposed to have identical acceleration going off the animation, [...]

This is an assumption, acceleration isn't actually discussed anywhere in the show and the specs don't actually cover it.

All of your conclusions here are based on rather spurious reasoning that assumes a minor weight variance is enough to require stats to change.


ShadowLogan wrote:
Its also possible that the tanks are as large, but standard operations only fill it by 1/10th of volume (in RT, though the same mass as the OSM) due to overall supply of the fuel and/or no operational need to fill the tanks to full.

Generally speaking, system endurance is for a full fuel load... this would imply that the VF-1 in RT has an actual operating time of 4.8 hours not 48.


ShadowLogan wrote:
They have to destabilize the SLMH to be useful in the engine/reactors, [...]

No they don't... in fact, keeping it stable would be damn near ideal if you're using inertial confinement fusion since you've essentially got precompacted fuel at STP. Normally inertial confinement fusion relies on pellets of frozen fuel to achieve this precompression. Aerosolizing it would also be easier for a magnetic pinch fusion reactor if it were kept stable, it could be injected directly into the plasma stream as a high density fuel. Destabilizing it would be the LAST thing they'd want to do with the stuff.

_________________
Macross2.net - Home of the Macross Mecha Manual

Zer0 Kay wrote:
Damn you for anticipating my question. I've really got to unfoe you, your information is far more valuable than my sanity when dealing with your blunt callousness. :)


          Top  
 
Unread postPosted: Fri Oct 25, 2019 12:20 pm
  

User avatar
Knight

Joined: Thu Mar 30, 2006 10:50 am
Posts: 6163
Location: WI
Seto wrote:
On that, I am not so sure... surface-based mining operations aren't really necessary when you can just tow asteroids back to your space station and mine them in relative comfort and safety. All the benefits, none of the drawbacks. The UEEF's operations were pretty much exclusively on habitable planets in Sentinels. Optera's the closest they're ever shown to visiting an uninhabitable world outside our own solar system, and even that's still capable of supporting human life with no protective gear whatsoever... it just suffered a total ecological collapse thanks to the bombardment of the planet's surface.

Re: mining
It likely is going to be complicated with each approach with their own pros and cons. Precedent (ALUCE) favors the UEEF/UEDF using surface worlds over asteroid towing or using mining ships (neither have any precedent in RT AFAIK being used by the UEEF/UEDF).

Re: Sentinel Worlds
How wide are we casting our source net? Optera and Tirol are technically the only Sentinel-era worlds re-visited in canon. We don't know how habitable Haydonite world is either in canon.

Drawing from older depictions (pre-2001) Garuda isn't exactly habitable (they might as well be on an uninhabitable world). Praxis self-destructed (genesis pits, though prior to this was habitable). Spherian biology leads me to think the planet maybe hospitable, but not habitable. Peryton and Kabara are habitable (though IIRC Kabara is heavily polluted requiring protective clothing, then you have Peryton's "curse"). Haydon-V was "habitable" via artificial means (IIRC Novel #18, since Haydon-V was a ship).

Seto wrote:
This is an assumption, acceleration isn't actually discussed anywhere in the show and the specs don't actually cover it.

All of your conclusions here are based on rather spurious reasoning that assumes a minor weight variance is enough to require stats to change.

The Minor variance is based on the math. If the RT version is more massive (just due to fuel, and ignoring the rounded mass), it must generate more force/thrust to achive the same acceleration in a given scene. (its certainly possible in the animation they aren't using Maximum Thrust, which would negate the issue but as you say it isn't addressed in show dialogue)

I don't object to going off the OSM spec, but the main issue is how to reconcile the mess HG caused by going off from the OSM. It isn't as simple as you make it out to be since multiple values change as result, we can "force" some specs to remain OSM true and allow the others to change. However there is no single value from the OSM that has to be "forced" to remain the same, such a "force" isn't really a "force" it's a choice given the specs interconnected nature (via the math). At best in this situation I think the only thing we can really do (absent more input from HG) is provide various option configurations that "force" some values to remain OSM-true while allowing others to change for RT.

Seto wrote:
Generally speaking, system endurance is for a full fuel load... this would imply that the VF-1 in RT has an actual operating time of 4.8 hours not 48.

The only other way to reconcile the tank size is that the RT version is a multi-fuel fusion design (D+He3 example) and the tanks are "nested" (one inside the other) or use a common bulkhead (externally it might appear as one large tank).


          Top  
 
 
Post new topic Reply to topic



Who is online

Users browsing this forum: No registered users


Display posts from previous:  Sort by  
Jump to:  

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum


Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group