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Aerobraking mechanics


Guest LoSboccacc

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Alright, I\'m testing this now. I\'m in an 875 km x 655 km orbit, coasting downward. I\'m going to point the capsule away from Kerbin while it coasts through the atmosphere, and see what happens.

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Curious. Might be evidence of some lift, of the quite unphysical variety that we have today... but I\'m not really sure. And I understand that capsule lift isn\'t yet implemented, so it would be an unwanted side effect... should test it myself, I suppose.

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It seems to me (an admitted amateur enthusiast) that if you enter the atmosphere at the right (or wrong, depending on perspective) angle and velocity, gravitational acceleration will override aerobraking. The first post never mentioned speeds, but if the apokee is increased after the first atmosphere intercept, then it seems likely the net deceleration from aerobraking was less than the net acceleration from gravity. By the time the capsule was again going against rather than with gravity, it was already out of the atmosphere and not being slowed by air anymore. Remember that the Voyager probes aren\'t using any propulsion - they used planetary gravity wells to slingshot themselves to higher speeds.

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Sorry, no. Gravity fields conserve energy; you do not get 'more energy', then 'less energy' around periapsis. Slingshot effects only work by stealing orbital velocity, not within the frame of reference of the parent body. Also, the apokerb was never claimed to increase; that would be an immediate 'Houston we have a problem' scenario. It was perikerb.

I\'m in a similar boat, of course. That induction from instantaneous effects is obviously superior to my reasoning, and shows my model justification up for the halfbaked nonsense that it is. I went halfway to calculus when I should have gone all the way. If perikerb increases, it\'s a bug.

I still intend to help test the response to capsule orientation, but I haven\'t had time to fly for a week. I\'ve stolen a bit of time to try some things with Cheat Engine which may allow better accelerated testing. We\'ll see.

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