Vertical launch spaceplanes

[BattleMetalChris]

I have a 'rescue a kerbal from Kerbin orbit' mission.

Whilst putting together a 2-seater rocket to go and get him, I thought it'd be fun to use an initially unmanned rocket and have him ride back down alone.

Then I thought it'd be even more fun to send an unmanned spaceplane up to get him, so he could fly down. I started by just building a plane with a liquid engine behind it, and a booster stage to get it up into orbit.

Predictably, as soon as it got fast enough for the air to flow over the wings, the whole thing flipped over backward with disasterously hilarious results.

My question is, is there any way of feasably launching a space plane vertically without the wings causing it to flip out? I tried using a procedural fairing to cover the whole aircraft stage, but it still did it.

I'm using FAR.

[LethalDose]

No part in the game causes asymmetric lift (e.g. flow over the wings creating lift), it's all deflected air that leads to lift, so even in FAR, it's not your upward velocity causing you to flip.

The problem is almost always the vector of thrust is offset from the CoM at some point during the burn. The "brute force" solution is to load up the shuttle with reaction wheels. More refined solutions are totally dependent on designs.

[Captain Sierra]

pictures are worth a thousand words, so some images would be massively helpful. If you are attempting to launch the thing STS style, than LethalDose has already answered your question. If thats not the case, again, images are worth a thousand words.

[magnemoe]

Taking off is easy, you need an TWR higher than one and not 1.01, also jet engines are less effective at takeoff so aim for something closer to 2.

You want the lift from the wings once you get up to some attitude, I found it more stable if climbing around 80 degree. At around 20 km you want to gain speed flying horizontal anyway and need wings.

Landing is an larger problem. My solution is to fly low and slow, then I activated two rocets at the nose to tip the plane vertical, this will also kill horizontal speed, release parachutes and you float down, use the engines to slow down to an soft landing.

This was done with this x-wing spaceplane on Laythe. Here I needed vertical landing because of the ruged terrain and the water.

[KerikBalm]

I like to do vertical launch space planes too, that way I can design them easier for Vertical, tail sitting landings, which I find to be the easiest way to land them on other bodies.

It sounds like you are not making an SSTO, but rather using a booster rocket, and then you've got a return orbiter.

In this case, its having the CoL in front of CoM that is causing the problem. My solution has been a "puller" configuration. Its a bit ugly with a blunt nose (if only I could attach something to the shielded docking port in the editor), then attach something to the front of the nose and mount two rockets radially to that (with parts to give spacing if needed). I like to do a liquid fuel tank, and then have fuel lines going to radial mounted LFO tank with LF engines underneath. Underneath the LFO stage, I have SRBs.

So it goes: SRBs fire, decouple, LF engines fire, and should get you to space, where you can decouple the spaceplane (or other big draggy thing that makes a rocket unstable if it is on the front) without causing problems (trying to decouple in the atmosphere can cause a lot of problems, obviously, if the detached part is in front of your, and you still need to thrust more).

I think I ended up doing that when I tried to launch this thing:

[BattleMetalChris]

Thanks guys

Yeah, I think you're right, it's a combination of COT being off-centre, and COT being behind the COL.

I might try something like a Star Wars podracer tonight, with the orbiter behind the ascent stages.