Balancing a Space plane on a rocket

[automcdonough]

I bet with some fancy flying you could do it, would be some balancing to keep the prograde vertical. I always just used MJ, didn't think to try it this way, but now with the time slowdown keeping things controllable it might be worth a shot.

[0x0h]

Now, all of that said, I actually have been experimenting with true NASA shuttle designs with no ridiculous gimmicks like counterweights or SRBs on the shuttle itself, and as others have pointed out, there's only one way to really make it work, and that's by angling the shuttle's main engines so their direction of thrust passes through the center of mass on the shuttle stack.

Sounds easy, right? Not so much since your center of mass is going to shift as you consume fuel from your main tank. This means you'll either need to be a design savant, or you'll need some way of angling the engines in flight or at least controlling their thrust on an individual basis. You may be a design savant. If so, I'd love to see your shuttle design.

Being able to move the thrust vector of the engines in flight and controlling thrust levels on an individual basis would be the best approach, but it is also possible to make COM shift using properly timed firing and shutdown of engines. That said, any shuttle-like design that's not prepackaged in a mod pack is going to have concessions to make. Stock? Forget it if you want a cargo bay or any fuel in space (lookin' at you, Mk 3 Fuselage). More then 3 crew? Have fun fitting a 2M round peg in a ~1.3m square hole. SRB boosters? Not unless you mod the heck out of them. True to the mechanical design of the shuttle? Prepare for it to look like something that came out of a blender. True to the aesthetic design of the shuttle? Three LTV45s aren't going to get you far once your boosters burn out and you've got to lug that external tank.

Me? I'm happy with something shuttle-like that's pleasing to the eye and somewhat functional.

[MDBenson]

One thing I'd give my eye teeth for is a good flyable version of the Dreamchaser CTV. It's so cool looking, like a baby space shuttle.

I also have tried, I got the thing to orbit using MechJeb 2.0.7 as an autopilot but promptly found my plane had far too little lift when it got back to Kerbin!

[MDBenson]

There's always Bobcat's Kliper Soviet CTV in his Soviet pack. Looks pretty neato. You also get a Soyuz for it so I have an excuse to use that cool 'star of Russia' booster separation

[rhoark]

I finally got this working (B9 obviously)

A couple of Mk2 fuel tanks counterbalance the fuel weight, which drains from the orbiter and counterweight before the center. Engine placement and activation pattern counter the dry mass imbalance. Action groups 1-5 activate/deactivate engines to move the center of thrust progressively towards the orbiter side. (1-5 is each pressed once on the way to orbit, no pulse width modulation or anything like that.) The "boosters" are actually engines under structural fuselages and are not dropped. At 30s to apoapsis it does a partial circularization, raising periapsis to about -100m and delaying apoapsis a couple of minutes. The orbiter is then refueled to 2000 potential dV and the tank dropped. It carries up to 4 kerbals, but despite the appearance of a cargo bay does not carry cargo - the bay is full of monopropellant and avionics (SAS, RemoteTech control and command, antenna, ProgCom, sensors, graphotron, chatterer, solar panel, and docking port).

Full album on imugr

Edited May 15, 2013 by rhoark