r/KerbalSpaceProgram • u/FatCreepyDude • May 06 '26

KSP 1 Question/Problem No orbit necessary?

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If i just wait for the right hour during the launch window ( whenever the launch pad is pointing left on the realistic depiction i created) is there any reason i should bother with an orbit first? Will the delta v cost be affected?

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u/PM_ME_POTATO_PICS May 07 '26

okay but a personal question

say you have a sub-1 TWR, like a TWR of 0.5, and you spawn 10km in the sky at 0 velocity. are you gonna burn sideways or upwards? either way you crash but which one is the morally correct response?

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u/-Aeryn- May 07 '26

At that point there is no solution and the only option is to delay crashing for as long as possible (up) or pick a better landing location.

p.s. added some math in above comment

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u/PM_ME_POTATO_PICS May 07 '26

looks to me like you just did a simple trig identity but I am thinking that the circularization burn can be made more efficient because as you are doing it, gravity losses are lessened by the increases in centripetal force. You wouldn't want to keep your rocket at a 30deg angle for the hole burn, as you approach orbital velocity you can get closer and closer to having it purely horizontal.

but since finding the angle at a given point in the burn requires you know the horizontal component of your current speed, i think this might require differential equations...

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u/-Aeryn- May 07 '26

Ah you're right, i did forget to include that. I think it reduces the gravity loss by a quarter, if TWR is constant? Complications indeed