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SSTO Alpha Heavy

68.5t to 100 km orbit (max mass 196 500kg)

The Alpha Heavy spaceplane is a Single-Stage-to-Orbit, probe controlled craft capable of lifting 68.5 tonnes into a 100 km orbit above Kerbin. With the payload and main engines centred the craft is well balanced and easy to control at all stages of flight.

Slightly better performance is possible with a continuous climb at 10 degrees; however, heating gets very close to the tolerance with heating set to 120%. For safety the suggested flight profile pitches up to 15 degrees at switch over to close cycle.

The suggests re-entry profile will overshoot the landing site slightly. Once speed drops to mach 4.5 (1500m/s) pitch up to increase drag as needed to reach the target.

If coming in short and the jets are needed, use them as high up as possible where the atmosphere is thinner to make better use of the limited fuel.

Payload Capacity: 68.5 t
Cost: 144 938.1
Parts: 95
Mass: 127 990 kg
Height: 8.9 m
Width: 22.6 m
Length: 36.0 m

Jet Engines: 8x CR-7 R.A.P.I.E.R Engines

RCS: yes
Power generation: Fuel Cell
Reaction wheels torque: 30.5

4 - cargo doors
5 - flaps rear [50%]
6 - flaps front [60%]
7 - intakes
9 - CR-7 engines
0 - CR-7 mode and intakes

- Extend flaps rear [5]
- Start CR-7s [STAGE]
- Takeoff rotation at 110m/s
- Retract flaps [5]
- 10 degrees pitch until max speed
- Switch CR-7 to closed cycle and close intakes [0]
- 15 degrees pitch until Ap reaches 50km
- Level to prograde when Ap reaches 50km
- Cut throttle upon Ap reaching desired
- Circularize

- Lower Pe to 40km over landing site
- 30 degrees pitch until speed drops to mach 4.5 (1500m/s)
- Switch CR-7 to air breathing and open intakes [0]
- Deploy air brakes as needed
- Deploy Flaps as needed [5, 6]
- Final approach at 100-150m/s
- Aim to land at 90m/s
- Deploy parachutes [STAGE]