The Roton, developed by Rotary Rocket Company, was an attempt at SSTO using a helicopter rotor for takeoff and landing. This particular concept was cone-shaped with a tip-jet rotor on top and an aerospike at the bottom. Unfortunately, they never managed to raise enough money for a prototype beyond the initial helicopter propulsion, let alone full SSTO.
In theory, there are advantages to this system:
- The helicopter "first stage" can get the rocket out of the thick atmosphere and its problems (unoptimised engines, aerodynamic constraints)
- The helicopter part can be used to slow down the craft and control its landing, instead of using extra mass for parachutes or fuel for a suicide burn
On the other hand, the thing does have a goofy Wunderwaffe look that make you wonder who the hell thought that could have been a good idea.
Beyond the failure (or the looks) of this particular project, could such a concept, using a helicopter rotor as a first stage and for landing, be made to work with decent performances compared to conventional rockets?