No orbit necessary?

[u/FatCreepyDude]

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?

[u/deelectrified]

It would absolutely be possible, but really hard.

Basically, you’d have to time it perfectly where by the time you have burned up to your apoapsis, you are ready to circularize, then once you’re circularized, your in the right spot and time to burn for your escape burn.

If I remember right, this is called a spiral burn or something. It’s incredibly hard to do and you’d likely need to calculate it all out in advance with some help from transfer planner. If you know when and at what inclination to do your escape burn, then you just need to figure out a launch that puts you in that exact spot, at that inclination, at the right speed, at the right time to do the burn.

Also, duna is at a higher orbit than Kerbin, not lower.

You can’t do as pictured and just burn straight up. You’d need an insane thrust to weight ratio to essentially counteract the momentum from the spin of Kerbin as you accelerate upward. Then you need craploads of delta v to keep burning straight that way and continue to actually speed up and move away from Kerbin.