Up to OJB's Aircraft List Glider I guess this glider was the quietest aircraft ever at Warbirds Over Wanaka. It wasn't completely silent though because as it flew past close to the runway it made a sort of swishing sound (yeah, I know, It's hard to describe). The glider was very graceful of course, and looked really nice with its bright white colour against the pure blue sky.  Gliders are capable of quite amazing performance. The best modern models can achieve a top speed of about 280 km/h (170 mph) with a typical stall speed of 65 km/h (40mph). Maximum glide ratio of open class sailplanes is typically around 60:1, which allows gliding long distances. The official record (set in 2010) is 2256.9 km.  Schleicher Glider Specs:
Note: I think this is the right model, please email me if I'm wrong
Crew: Two
Wingspan: 26.50 m (86 ft 11 in)
Wing area: 17.4 m^2 (187 ft^2)
Gross weight: 850 kg (1,870 lb) Sources: Wikipedia, FAI Records, Warbirds Over Wanaka 2012 Programme. | 
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