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Efficient atmospheric throttling


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So I\'ve seen it said that throttle efficiency is about equalising the forces of gravity and drag (or something). This is fine and all, even makes sense, but how exactly do we implement this in our every day designs?

I mean, I build a rocket, okay, great, but how do I know where to stick the throttle for max efficiency?

Even better, how would you go about designing a rocket so that max throttle just happens to equalise thrust and drag at max throttle?

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If you include MechJeb in your design, it shows you (in the accent autopilot stats) your delta speed distribution - how much was lost atm to drag, how much to gravity etc. This is not the solution, but it is a part of it, I believe : )

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yeah I notice that MJ shows the m/s you lsoe to drag etc. and also tends to throttle back on ascents, but I was kind of hoping for a bit more manual approach.

I think I saw some plugin that shows the stats of the rocket as you build it? Maybe that\'d be useful here.

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It depends on the rocket\'s design. If most-all parts have a drag of 0.2, this is the optimal speed vs altitude chart:

Altitude (m) Target speed (m/s) - rounded to nearest 5 m/s

0 97.3- you\'d better get a move on!

500 105 - you should be catching up by now!

1000 110

2000 120

3000 130 - usually the first benchmark I have time to look at

5000 160

8000 215

10000 260

13000 350

15000 425

16000 470 - most of us are at least thinking about staging and pitchover maneuvers by now!

..

32000 2250 - this is equal to the orbital speed, so by now you should be pushing over hard for orbit, and air drag is not as important above this altitude.

Rockets with relatively poor liftoff TWRs tend to be most efficient if left on full throttle the whole time. (They fall behind and stay behind these speeds)

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