Maximum Altitude

[Abadon Spectre]

This isn't something that is likely to come up in many games, but I got to wondering about it.

IRL, with aircraft and winged critters maximum altitude is primarily about air density. When there is no longer enough air to push against or pull in, then you just can't go any higher.
With thicker or thinner atmospheres a machine or winged creatures maximum altitude would change appropriately (I.E with no atmosphere they can't fly. Denser atmospheres have problems all their own.

Here's the question/s:
When dealing with magical flight (innate, spells, tattoos, etc...) that does not use wings or air manipulation what determines altitude when you are somewhere besides earth?

Is zero altitude based on sea level, gravity, magnetic fields, magic fields or something else entirely?

Each would have its own complications and possibilities. Any thoughts..?

[Library Ogre]

Generally, if there is no ceiling listed, I assume there is no effective ceiling save duration and life support. If you want to Fly as the Eagle straight up as long as you can, you will get 16.66... miles per level up*. 6th level caster? 100 miles straight up. 12th level caster? 200 miles straight up. Can you breathe there? Can you survive the radiation, low pressure, space debris, and any other dangers with being 200 miles up? Maybe not. But if you want to fly to Antares at 50mph, you can manage it if you've got the duration.

*PF Wizard spell, 20 minutes/level at 50mph.

[Abadon Spectre]

I probably should have specified that the questions pertained to magic with maximum altitudes (like the heart with large wings tattoo).

How much altitude or how fast it can be attained isn't what I am thinking about, but what the baseline for determining altitude is.

[Glistam]

I probably should have specified that the questions pertained to magic with maximum altitudes (like the heart with large wings tattoo).

How much altitude or how fast it can be attained isn't what I am thinking about, but what the baseline for determining altitude is.

It's magic - likely the only "baseline" for determining altitude was the mental frame-of-reference in the ancient mage who designed and perfected the spell. You could say those initial pioneers of magic limited the spell to that height because they thought that was high enough.

[Library Ogre]

In that case, I'd go with your gut, but bet they meant "above sea level"... which will cause its own problems.

[Axelmania]

Fly as Eagle got an altitude max in one of the Rifter erratas, just wish the Xiticix did.

[Mack]

I probably should have specified that the questions pertained to magic with maximum altitudes (like the heart with large wings tattoo).

How much altitude or how fast it can be attained isn't what I am thinking about, but what the baseline for determining altitude is.

For simplicity, I'd go with Above Ground Level (AGL). That saves you from worrying about a variety of problems.

Such as: the Heart with Wings tattoo has a altitude limit of 4,000 feet... but you're in Denver CO and the ground is already 6,000 feet Above Sea Level (ASL). Using ASL, the character can't take off at all. With Above Ground Level, he can ascend to 4,000 AGL (or 10,000 ASL).

This is a roleplaying game, not an aeronautics thesis.

[Mack]

Fly as Eagle got an altitude max in one of the Rifter erratas, just wish the Xiticix did.

The Xiticix ignore anything flying over 10,000 feet, so I use that as their limit (XI, p11). Imperfect, but workable.

[Axelmania]

Powers Unlimited's minor super ability which gives you insect wings (dragonfly, wasp or butterfly) also has an altitude limit of 10 000 feet which conveniently matches.

Although the 'winged flight' one from the core book which doesn't shrink you, I think you can select insect instead of feather for that and I don't know of any height limit for it, and it's probably closer to Xiticix since they're human size, not Winsome-Wasp-Sized.