Better atmosphere models for very high altitudes?

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BreekiBoots
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Better atmosphere models for very high altitudes?

Post by BreekiBoots » Sun Mar 25, 2018 1:03 am

I've been doing some excursions into the upper atmosphere recently, and one thing I've noticed is that the near-vacuum above 30 km seems to be making a hell of a lot of drag. Is there any way I can fix this?
What I believe is happening is that the standard atmospheric model ends at a lower altitude and continues indefinitely upwards at a uniform pressure and density. I may be wrong, but I really just want to fix this little inaccuracy.
What is there that I can do? Cheers

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waspe414
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Re: Better atmosphere models for very high altitudes?

Post by waspe414 » Sun Mar 25, 2018 1:17 am

The atmosphere model is hardcoded in the .exe and can't be modified by players. Above 36km is a vacuum, and flight is purely ballistic; thrust and maneuvering do nothing to change trajectory. The threshold is hard, so your aircraft produces some amount of lift at 118110ft, and zero lift at 118120 ft.
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Re: Better atmosphere models for very high altitudes?

Post by BreekiBoots » Sun Mar 25, 2018 2:42 am

So I suppose what's actually happening is that the aircraft ceases to produce thrust above 118120 ft. Are there any aircraft-specific variables that change how the thrust output responds to altitude, or is this hardcoded too?

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Re: Better atmosphere models for very high altitudes?

Post by waspe414 » Sun Mar 25, 2018 2:51 am

Thrust to altitude is fixed, though the curve for jets is different than propeller planes. The only thing we can change in the .dat file is the overall thrust of the aircraft. Decaff has done some work reverse engineering this, available here: https://sites.google.com/site/ysdecaff/ ... c-research
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Re: Better atmosphere models for very high altitudes?

Post by BreekiBoots » Sun Mar 25, 2018 3:22 am

So no accurate behaviour for rocket planes, I suppose. Anyway, thanks for clearing this up.

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