Here's it's grandfather; the DFS 332.
Developed in wartime Germany as a 'flying wind tunnel', originally as a glider,
but also to use rockets to attain higher test speeds and durations.
Source 'Paper Planes of the Third Reich', Toros publications.
Also, the Fouga G.M. 88R Gemaux, built in 1951 as an engine testbed.
http://www.fortunecity.com/tattooine/farmer/120/twin.html
cheers,
Robin.