The Dornier Do-33 was the first project of a combination of a rocket and a helicopter. The unmanned, fully automatic, erector-started and recoverable drone was intended to be used as tactical short-range surveillance vehicle in all kinds of weather (never produced). When cruising, the 3 rotor blades at the pivotal tail that can be shortened are in idle longitudinal position and serve as an empennage; when hovering, they were turned and lengthened in telescopic sections driven by 3 unfolding nozzles. This complex vehicle was started at a time when Dornier was still experimenting with radical designs before building a series of airliners. It was before Reunification, under W German budget and so it never proceeded past a prototype. Decades later another radical Rotary Rocket idea also failed to get any funding. The Do-33 now sits in a museum in Germany on display as a curiosity of sorts.

http://www.hubschraubermuseum.de/exhibition/images/shop/hub_do33_big.jpg