Brief development history
In 1955 the ban on aircraft development and production in Germany, a result of world war II, ended. The new Ministry of defense discussed the need for an interceptor aircraft. The geographic situation of Germany as a NATO front state made high top speed and climb rates necessary. In 1956 selected companies including Heinkel and Messerschmitt began with their studies. The increasing performance of modern supersonic jet aircraft required long and well prepared but vulnerable runways. Therefore in autumn 1957 the ministry claimed additional VTOL (Vertical Take-Off and Landing) capability for the aircraft. Under the condition that Messerschmitt, Heinkel and Boelkow work together a contract for development and construction of five prototypes was announced. The three companies then joined works in the Entwicklungsring Süd (EWR) in February 1959.
But within NATO a workshare was arranged which assigned the interceptor role to the former world war allies whereas the German Luftwaffe should target enemy aircraft on their airfields. The changed mission profile made high fuel capacities necessary for low level flight over long distances and led to the VJ-101 D design study. However this project was never realized when NATO and Luftwaffe lost their interest in VTOL capability in the mid 60ies.
Nevertheless the work on the VJ-101 C continued. The X1, equipped with six Rolls-Royce RB-145 without afterburner, made its first hover flight in April 1963. Vertical take-off and the transition to aerodynamic flight by swivelling the engine pods on the wing ends were safe and confirmed the selected VTOL-concept. In July 1964 the sound barrier fell when the aircraft reached Mach 1.08. With this flight the VJ-101 became the first VTOL-aircraft in the world to reach supersonic speed. In September the X1 was totally destroyed during a conventional take-off. The pilot survived without injuries. A malfunction in an electronic system initiated the crash but the VTOL-components where not responsible.
Ground tests with the X2 began October 1964 followed by the first hover flight in June 1965. The major difference between the two experimental aircraft were the engines on the wing ends of the X2. The RB 145 Rs were equipped with afterburners. They improved the aircrafts flight performance and take-off weight but increased the problems with recirculation of hot gases and ground erosion during vertical take-off and landing. The X2 was later damaged in a hard landing when the landing gear broke.To reduce the danger of engine stalls initiated by hot gas recirculation and to avoid the heavy ground erosion when using the afterburners a new take-off procedure, so called RVTO - Rolling Vertical Take-Off - was developed and successfully tested. With the engines turned 70 degrees the aircraft lifted off after 3 m rolling and reached 15 m altitude after 40 m. In the same way landings with afterburner needed only 50 m of runway.
Meanwhile a memorandum about the joint development of weapon systems between the German and US-government was signed. One result was the US/FRG ( FRG = Federal Republic of Germany ) design study for an advanced V/STOL tactical fighter weapon system (AVS) as an F-104G successor. The EWR cooperated with the Fairchild Hiller Republic aviation division and the X2 participated in this program as the only available flying test bed for advanced V/STOL concepts and flight control systems. But flight-tests had to be stopped in June 1971 when the life-time of major aircraft components ended. The AVS program was terminated, when VTOL-capability became unimportant for the air forces.
With the VJ-101 C, VAK-191 B and Do-31 a complete V/STOL-aircraft family for intercept, strike and transport missions was developed. Although the military requirements referring to the need of an interceptor with VTOL capability had been already changed when the VJ-101 C reached the flight test phase, the experiences from this project helped the German aviation industry to become familiar with modern aircraft development. It allowed the German industry to participate in the European Multi-Role Combat Aircraft (MRCA)-project which later became the Panavia Tornado.
History of the first experimental aircraft VJ-101 C X1
Tests with the aircraft coupled to the ground with a telescope stand begin
10.  4.
First hover flight
31.  8.
First aerodynamic flight
First complete transition from vertical take-off to aerodynamic flight back to hover flight for vertical landing
23.  4.- 3.5.
Flight demonstrations during the German international air show ILA in Hannover
29.  7.
First supersonic flight, Mach 1.08 reached
14.  9.
X1 crashes during a conventional take-off. The pilot ejects safely. Malfunction of an electronic component is responsible for the accident
History of the second experimental aircraft VJ-101 C X2
12.  6.
First hover flight
12.  7.
First aerodynamic flight with afterburners
First vertical take-off with afterburners
First complete transition from vertical take-off to aerodynamic flight back to hover flight for vertical landing with afterburners
19.  9.
First rolling vertical take-off with afterburner from a regular runway
21.  4.
First supersonic flight, Mach 1.14 reached
  7.  6.
Flight tests finished
The aircraft is part of the aviation exhibition of the Deutsches Museum in Munich