F-104CCV (control configured vehicle) 98+36 ready to land

MBB became interested at an early date in highly-maneuverable aircraft. A Fokker-built F-104G (23+91, later renumbered 98+36)
was modified by MBB as part of a five-year research program into control configured vehicles (CCV) and fly-by-wire technologies.

Natural stability was replaced with computer-controlled fly-by-wire systems that allowed the aircraft to be made unstable.
This instability could then be controlled to provide extra agility.
The aircraft was provided with a triple-redundant fly-by-wire system in 1977.

The transition from the naturally-stable Starfighter aerodynamics was taken in gradual stages, first by adding ballast to alter the centre of gravity.
In 1980, a complete F-104 tailplane section was then grafted to the spine on the upper fuselage forward of the wing to further destabilize the aircraft.
Fairings were added over the wings, and the aircraft was marked with extra Day-Glo panels for high visibility.

20 percent negative stability was finally achieved within the specified limits of Mach 1.3 and 650 knots by the time the trials were successfully concluded.
The data gathered was of great assistance to the design of the European Fighter Aircraft (EFA), known now as Eurofighter "Typhoon"
and was also used during the development of the Rockwell/MBB X-31 testbed.

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