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Is duna aero brake deadly?


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Overheating on Duna is not a problem.  I'd recommend a heat shield to play it safe but, for a typical aerocapture, you won't burn off much ablator.  Entry from orbit doesn't need a heat shield at all.  I have found that the aerocapture periapsis is pretty sensitive your entry velocity and the ballistic coefficient of your vehicle.  If you have a relatively slow intercept with a low ballistic coefficient, you'll probably need a periapsis of about 20 km.  If you have a fast intercept with a high ballistic coefficient, you'll probably need a periapsis of about 10 km.  If you miss on the periapsis, you may not aerocapture at all or you may not pull out of the atmosphere.  I'd recommend at practice run and be prepared to revert/reload if you get it wrong.
 

Edited by OhioBob
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You can certainly aerobrake on Duna, it's just a question of how fast you're coming in.  Duna is relatively forgiving as aerobraking goes.  If you're coming in at interplanetary speeds, it's generally a good idea to bring a heatshield; that's about it.

The hard part with Duna is not so much aerobraking, but slowing down enough to land; the air's so thin that it's easy to faceplant while you're still going far faster than parachutes can handle.

Drogue chutes can help a lot; so can designs that have body lift (or just outright wing lift) to give your craft more time to slow down.

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Not at all. Heat isn't an issue even without heatshield, thin atmosphere may be.

I aerobraked a rover without heat shield nor chutes and ended with only 140m/s to suicid burn for landing (a bargain).

The issue is about drag. if your vehicle isn't draggy enough, you won't loose enough speed, even to open chutes and you'll crash. Going to Duna with just regular chutes is dangerous. Use drogue chutes and/or fuel.

For example : don't enter Duna atmosphere on a retrograde attitude, don't hesitate to face radial or normal to increase drag as much as possible. Favour flat landers...

For example : I tested landing with Kerbal-X. I used the engines to slow down so chutes could open safely. They were successfully partially open but even though, I was still increasing speed and chutes were destroy after.

The new part which will be introduced in 1.1 (10m inflatable shield) will be a big bonus for Duna landings (even not reusable)

 

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I've found that speeds exceeding 3700m/s either result in explosions or not enough braking to capture.

However the atmosphere is so thin that you can do a powered aerobrake (using rockets and burning retrograde while in the atmosphere). Just remember to hit F5 and do a quicksave.

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