Wanderfound's Spaceplane Piloting Guide

[Wanderfound]

Spaceplane Piloting 101:

1) Get to 20,000m however you like. Especially with larger planes, a shallow ascent path (vertical speed kept to about 100m/s the whole way up) is most efficient, but fast overpowered sport things can often get away with a vertical climb to 20,000m. The more horizontal speed you have at 20,000m, the easier you'll find things above 20,000m.

2) When you get to 20,000m, level off and build some speed. You want to pile on as much horizontal velocity as possible while you make your ascent to 30,000m. Keep your angle of attack (the angle between where your nose is pointing and the direction in which the plane is actually moving, shown by the prograde marker when in surface mode) and climb rate low; by the time you hit 30,000m, they should both be around 10 or so. A low angle of attack reduces drag and helps your intakes work better. The low angle makes you climb slower, but that's okay; you need that time to get up to speed. As you go faster, the angle of attack required to maintain a given climb rate reduces, but as you go higher, the thinner air means that the angle of attack required to maintain a given climb rate increases. If you do it right, these two factors will roughly balance each other out and you should gain the necessary speed and altitude in a single smooth climb. However, a plane with some aerodynamic or piloting flaws may need to bounce up and down between 20,000 and 30,000m a couple of times while building speed before the final push.

3) Somewhere between 20,000m and 35,000m (exactly when depends on both plane and piloting), you'll start to run short of air. Don't switch to rockets immediately. If you've got multiple engines going, shut some down to concentrate the available oxygen into the ones you keep running. If you've already shut down as many as you can, throttle back a bit. You can dramatically increase your jet-only altitude by doing this, and once you get up to serious height the thin atmosphere means that you only need a tiny amount of thrust to accelerate.

4) Keep this going for as long as your plane and your patience can tolerate. A well-built and -flown plane should be able to get over Mach 4.5 and 30,000m in a single attempt on jets alone. Once you've wrung as much speed and altitude out of the jets as possible (you want at least Mach 4 and 30,000m), light the rockets. If you have both jets and rockets, don't shut down the jets immediately; the thrust of the rockets will drive a ram-air effect that kicks the jets back into life for a while. Keep the rockets burning until your apoapsis exceeds 70,000m, then shut off and coast until it's time to circularise. Point prograde and close your intakes while coasting to minimise drag.

4a) If you've got nuclear rockets, shut down all other rockets above 35,000m as soon as your apoapsis is a comfortable time margin ahead of you. Reengage boost rocketry if necessary to stop the apoapsis being passed, but otherwise fly on nuclear alone.

A good plane and pilot should be able to get the apoapsis to 70,000m with less than a minute of rocket power. Done properly, it requires very little fuel. But if you try to brute-force it from lower speeds and altitudes, the atmospheric drag is going to drain your oxidiser tanks before you get anywhere near orbit.

If you're having trouble with design rather than piloting, give http://forum.kerbalspaceprogram.com/threads/90747-Kerbodyne-SSTO-Division-Omnibus-Thread?p=1434926&viewfull=1#post1434926 a try.

* Send a Kerbal to the beach at the east end of the runway. Plant a flag. You now have a landing beacon. Set this flag as a target.

* Burn retrograde until your trajectory intersects the ground on the west side of the KSC home continent.

* As you descend, keep your nose within 10° of prograde and immediately correct any stall. You can afford a much larger AoA at higher altitudes, but you should still avoid stalls and close to prograde as soon as you start to feel the atmosphere through your controls.

* Pull up as sharply as you dare. Aim to level out at ~25,000m.

* Check your distance to KSC. If it's over 200km, slowly descend in order to hit 6,000m at the mountains west of KSC (which are about 5,000m tall). If it's within 200km, begin S-turns to wash off speed and altitude.

* S-turns. First, decide how urgent the turn is and whether you also want to drop altitude. If the turn is urgent or you want to drop, stand the plane on its wingtip, keep the nose on the horizon and pitch up (carefully). If less urgent or you want to maintain altitude, roll to ~45° and pitch/yaw the nose around, monitoring climb rate and controlling it with pitch as you go.

* Make sure the flag is still set as target. If your prograde and target markers coincide, you're heading for the end of the runway. If they aren't on a bearing of 90° while you're doing this, you're coming in at an angle. Fly to the side until the target indicator is at 90°. Then fly towards it.

* Get lined up, low and slow as soon as possible. As soon as you're over the mountains, start doing S-turns and drop to the deck. Pull it down to <150m/s and <500m altitude, then point at the runway and level your wings. The shallower the approach the better. Keep engines on minimal throttle to hold speed constant.

* Avoid any drastic manoeuvres over the runway. You'll probably overdo it and make things worse.

* Watch your VSI (vertical speed, to the right of the altitude meter) and keep it to 5m/s or so. Triggering spoilers will increase it; balance the spoilers will gentle pitch-up.

* Don't be afraid to wave off and go around again if it gets messy. Also remember that the paddock beside the runway is an easier landing strip than the runway itself.

* Be ready to hit the brakes and do some delicate steering as soon as you land. Stick to the middle of the runway if you're using it. Trigger RCS and Vernors and use the "N" key for retro thrust.

Edited September 29, 2014 by Wanderfound

[ratchet freak]

2 more hints: use flaps to allow for a slower flying speed

add another marker further to the west (in the mountains) that you can aim for before turning to the runways so it's easier to line up