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The title says it all.

A big heavy heat shield will mean a whole lot of wasted delta-v if it's not required to re-enter on Duna. With Duna's low gravity and hence low orbital speed, combined with sparse atmosphere, is a heat shield necessary?

Re-entry on Duna

Coomie
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1 Answers1

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No, a heat shield is not necessary for landing on Duna. At least not when you go into orbit first. It might be necessary when you do a direct descent from interplanetary transfer speed, but in that case the bigger problem is slowing down fast enough before leaving a crater.

One thing to consider when landing on Duna is that with the new aerodynamics model, parachutes are even less effective than they used to be. They can help, but you should definitely plan a retro-burn before ground contact and/or invest in heavy landing gear.

Philipp
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  • I thought that would be the answer. Even coming in from interplanetary transfer should be survivable without a HS if you come in at the right angle, right? – Coomie May 11 '15 at 08:11
  • @Coomie That depends on how you define the difference between a "direct descent with the right angle" and "entering orbit with aerobreaking a bit too close so you slow down too much and fall into the atmosphere" (did the latter accidentally on my last mission to Duna and the craft landed unharmed). – Philipp May 11 '15 at 08:15
  • I don't know about Duna, but I successfully landed on Kerbin with some sensitive equipment and without a heat shield, by using a couple drogue parachutes, reducing speed by very gentle aerobraking (multiple passes through upper atmosphere) and then deploying normal parachutes after slowing down to <1000m/s without ever entering the "flaming" phase. If you're at orbital altitude but slow enough, descent on a parachute will be safe. It's the aerobraking against the orbital speed that does most of the damage. – SF. May 28 '15 at 15:05