The foot launched Ruppert Archaeopteryx Weighs 120lbs (56kg), first built in 2001, there have been 18 made, and new ones can be purchased. However, there was a lighter glider weighing 106lbs (48kg) in 1989, called the Aériane Swift.
https://en.wikipedia.org/wiki/Ruppert_Archaeopteryx
compared to:
https://en.wikipedia.org/wiki/A%C3%A9riane_Swift
The Lighthawk glider is heavier at 150lbs (68kg), but has much better aerodynamics, with 0.36m/s sink rate compared to 0.5m/s sink rate.
https://en.wikipedia.org/wiki/Glidersport_LightHawk
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