Brachistochrone trajectory

[Crashonaut]

assuming you can get enough fuel aboard a ship, or use a highly modded engine, is the Brachistochrone trajectory an option in KSP?

[glacierre]

Surely you could program mechjeb to burn+steer so you follow such trajectory. The question is... why?

[Aghanim]

I know an engine that have enough dV for the trajectory, this: http://forum.kerbalspaceprogram.com/showthread.php/28428-Orion-aka-Ol-Boom-boom

Try it yourself

[maltesh]

I've brachistochroned the Mun from LKO on an LV-N equipped spacecraft, a couple versions back. Made the landing in just under an hour from launch. Brachistochroning Minmus is probably feasible without going /too/ crazy on the build, brachistochroning interplanetary targets probably does require something pretty incredible.

[Der Kosmos]

I've brachistochroned the Mun from LKO on an LV-N equipped spacecraft, a couple versions back. Made the landing in just under an hour from launch. Brachistochroning Minmus is probably feasible without going /too/ crazy on the build, brachistochroning interplanetary targets probably does require something pretty incredible.

The plasma engines in KSP interstellar make this a sensible proposition.

[cantab]

You'll need either good TWR to go with the delta-V or a mod that allows thrust under higher timewarp, since for a true brachistocrone you need to be accelerating through the whole journey.

To give some numbers, let's say you want to do the shortest interplanetary trip, Kerbin-Eve. That's a trip of 3.7 x 10⁹ m. You're going to flyby or impact so you don't even care about turning round and slowing down. And you're happy with a 16 hour (57600 s) burn - reduces to a minimum of 4 hours with max physics warp and no lag.

s = at²/2

a = 2s/t²

a = 2.2 m/s²

A relatively modest acceleration requirement actually, but a ship that can sustain that continuous acceleration for 16 hours? I'd like to see it. (And not counting warp drives )