Thanks to Koen Van de Kerckhove (hey, that's me. Now i remember how i met Stewart Midwinter by email :) ) for the following information:
The Hippie is a simple ultralight glider built by Start+Flug, also builders of the Salto. It first flew in 15 August, 1974. Some time later, there were already examples flying in five countries apart from Germany. The glider had three-axis controls through rudder pedals and an overhead stick. The glider's basic structure was made of fiberglass, with carbon-fiber reinforcements; the wings were plastic-covered, while the tail surfaces were fabric-covered. Later, a second version was built, with honeycomb-construction wings, a longer tail structure of aluminum tubing, an enlarged rudder, quick-connect fittings for the controls, and an enlarged seating area for the pilot. The glider could be broken down and carried in a box measuring 5 x 1.1 x 0.6m (a little shorter than a Swift box).
The design could be foot-launched, car-towed, aerotow-launched, or with some other assistance. (Rolling off a hill like the BUG was apparently not thought of). After a foot-launch, the pilot would draw up his legs into the hoop-like fiberglass seat fairing at the nose of the aircraft (see photo above), though's it not known how often the glider was ever foot-launched. The fairing also served as the landing skid (again, no wheel is mentioned). The designers recommended that for foot-launching, the following guidelines should apply:
Hill angle (in degrees) x Wind speed (in m/s) > 80
Applying this guideline, here are some examples of minimum wind suggested for foot-launching. On a shallow slope, the values seem a bit extreme!
Hill Angle Required Wind Speed
L/D ratio Degrees km/h mi/h m/s
1:1 45 6.5 4.0 1.8
2:1 27 11 7 3.0
3:1 18 16 10 4.4
4:1 14 21 13 5.7
5:1 11 26 16 7.3
7:1 8.1 36 22 9.9
10:1 5.7 50 31 14
15:1 3.8 76 47 21
Airfoil Wortmann FX S 02
Area 9.0 m2
Aspect Ratio 11.1
Weight 48 kg.
Max take-off weight 135 kg.
Wing loading 14.8 m2 / 3.0 ft2
Span 10.0 m
Folded length 2.4 m
L/D max. about 12:1 at 45 km/h
Min. sink 1.3 m/s at 40 km/h
Max speed (smooth air) 32 knots; 60 km/h; 37 mph