reveals secret Stealth fighter research
Jeziorski / Munich
Aerospace (DASA) has revealed details of a previously top-secret Stealth
aircraft research programme conducted in Germany during the 1980s.
The programme, known as Lampyridae (Firefly), or Medium Range Missile
Fighter (MRMF), was run from 1981 to 1987 by what was then Messerschmitt-Bölkow-Blohm
(MBB), under a contract from the German air force.
The work led to the eventual development of a three-quarter scale piloted
windtunnel model of a multi-faceted Stealth fighter. Former project
leader Dr Gerhard Löbert claims that the design “very probably”
had better radar characteristics than the Lockheed F-117 Nighthawk,
despite the F-117 having more than twice the number of radar-scattering
Windtunnel testing began on a 1:3.5-scale low-speed model and a 1:20-scale
transonic model in 1985. According to Löbert, these tests demonstrated
high-quality aerodynamic properties, despite the disadvantages of the
polyhedral airframe design.
preparatory simulator work, the manned ¾-scale model, 12m long,
with a 6m wing span, was “flown” 15 times in 1987, in the
German-Dutch windtunnel at Emmeloord. Complete flight cycles were simulated
in the tunnel’s 9.5m² test section, with the aircraft flying
at up to 120kt (220 km/h) and performing small-amplitude movements about
The project was driven by the idea that a future fighter could be lighter
and cheaper if it were so superior at mid-range that it could avoid
close-in dogfighting. The engineers’ task was to develop a configuration
with a forward radar cross-section in the X-band some 20-30dB below
that of a conventional fighter. Like Lockheed in its development of
the F-117, MBB used the principle of a polyhedral airframe, avoiding
right angels and curved surfaces which produced lift by generating a
system of vortices from its sharp leading edges.
In parallel to the design work, the company also developed a computational
method of calculating radar cross-section, which has since been used
to compare the Lampyridae design with available information about the
F-117. The radar cross-section was also tested on a full-scale, 16m-long
Details of the radar-signature tests are classified, but radar cross-section
targets “were met”.
International 8-14 March 1995)