This recent video from FES (Front Electric Sustainer) in Slovenia shows a relatively low-budget way to launch and sustain a sailplane in flight. This was uploaded to YouTube by Lumakaja on September 27, with the following commentary.
“This way of sailplane start, can make gliding much cheaper! Idea is simple: Use of FES after being airborne with help of auto-tow. Only a few sailplanes have high enough landing gear, so that propeller clearance on grass is not too small for safe self-launch. With minimal help of auto-tow than all FES equipped sailplanes would not need towing plane or winch any more to become airborne. All you need is FES equipped sailplane, usual car and about 120 meters (384 feet) of Dyneema rope. Such start could be used also on relatively short, let say 750 meter (2,460 feet) long airfields, which are otherwise too short for usual winch or car launch! If only short runway is available, then more powerful car is needed for good acceleration.”
The LAK-17 is a composite 15 (49.2 feet) to 18 meter (59 feet) span, single-seat sailplane made in Lithuania. A normal gross weight of 360 kilograms (794 pounds), can be increased to 500 kilograms (1,100 pounds) with water ballast.
The LAK’s round, symmetrical nose is necessary for FES use (it must emulate the sustainer motor’s spinner shape).
Towing by a Peugeot 307, a 105-horsepower hatchback, shows that even a fairly heavy sailplane can be sent skyward by modest means. The transition to electric power after the release of the tow rope seems pretty seamless, and the climb rate is impressive.