Firewheel (Feuerrad)
The Firewheel (Feuerrad) satellite was supposed for the first time ever to conduct plasmadiagnostic measurenments with high positional resolution. It should have been an active plasma experiment with huge Barium and Lithium clouds in an environment of weak magnetic field strength.
Unfortunately the satellite and its four sub-satellites were lost when the launch of the Ariane 1 rocket failed on May 23, 1980. It was the second launch of an Ariane rocket. Combustion instabilitiers in one of the Viking first stage engines caused an explosion shortly after launch.