(Engineering discussion) Best construction for a large two-stage spaceplane

[MedwedianPresident]

I am planning to make a large family of spaceplanes when I return home in several days; I will install FAR onto KSP to make use of more complex reentry and landing principles.

One of them will be a heavy spaceplane for LKO and MKO that will be launched piggyback using either a hypersonic jet or rocket stage, or more like a space shuttle. It will have fins at the ends of the delta wings. It will be with B9 parts.

It will be accelerated to around 1000 meters per second using the first stage (let us assume it is a tank with a medium engine on which the shuttle rides piggyback) and then will use the second stage attached to the back docking port to accelerate to 90% of orbital velocity. Around the docking port that will be revealed after the second stage is dropped will be 4 maneuvering engines, arranged in pairs, one pair on each side. The maneuvering engines will be used for circularizing and maneuvering in orbit.

After fulfilling the mission, the maneuvering engines will be used for deorbit and then, a slow descent in a very shallow reentry trajectory that will include entering and leaving the atmosphere multiple times for very slow velocity bleedoff and minimal G-forces if a delicate payload is to be transported. Landing will be on KSC runway.

Do you have any ideas for the construction or for the mission routine?

Edited November 17, 2014 by MedwedianPresident

[aleis]

With the amount of umpf your putting into the first stage and the second orbit stage is not really a plane any more. Mainly a rocket.

Think you could do better trying a Spaceship 1/2 approach instead using and airplane cradle to get to upper atmosphere then releasing a rocket that finishes the orbit

Otherwise just make a normal stacked rocket. Unless I'm not getting your design in my head right

[merendel]

One issue with the shuttle type design is its very difficult to fly it due to an off ballanced thrust vs COM that shifts as you burn off fuel. the RL shuttle has a gimble on the main engiens with a rather large range of motion that is computer controlled to compensate for this. We have no equivelent system in the stock game although there are a few mods that can fake it to a point.

If your set on a 2 stage design I would suggest you set your spaceplane on top of the rocket. A basic lifter stack positioned under the centerline of the spaceplane. Once stage 1 burns out you decouple and fire off your orbiters engiens to finish the mission. This will take a bit of design work in far as depending on wing design the lift generated could make it difficult to fly strait up without it wanting to list. I'd also recomend adding a 5th engien, a RAPIER on the centerline between the 2 pairs you spoke of. This will alow for more efficient air breathing flight on your return should you need powered flight instead of pure glide. You can put a stack behind them (cant on the normal jets) and you can run it in rocket mode as well during orbital maneuvers.

Alternitively you could make a spaceplane that lifts off horizontaly. Use the rapier engiens in airbreathing mode to get you up to altitude and to relatively high speed and then kick on the afterburners to send you into orbit. You could even potentialy sling some liquid fuel tanks under the wings that you decouple as your shifting from air mode to rocket mode.

Pure space shuttle replicas are just far too much trouble to replicate in this game. You can build them for looks just fine but makeing one that can actualy fly properly takes a ton of effort.