The Hall Ibex is an experimental, American, gull winged, single seat glider that was designed by Stan Hall and first flown in 1968.
Hall Ibex Wikipedia
The Ibex was designed by Hall to investigate the reduced wetted area of the pod and boom configuration, hands off spiral stability of a gull wing, and the low speed performance of wide NACA slotted flaps. It also features a V tail, 135 lb (61 kg) of water ballast and a 15 m (49.2 ft) wingspan to comply with FAI Standard Class rules. On one of its first flights the Ibex showed significant tail flutter. Initially Hall considered replacing the tail with a conventional empennage and tail but ended up moving the ruddervator counterweights from the tips to the roots which eliminated the problem.
The Ibex was still flying in 1980 and was eventually donated to the National Soaring Museum.National Soaring Museum -1 in storage
Data from Sailplane Directory
General characteristicsCrew: 1
Wingspan: 49 ft (15 m)
Wing area: 125 sq ft (11.6 m2)
Aspect ratio: 19.2
Airfoil: FX61-163 Root, 60-126 Tip
Empty weight: 580 lb (263 kg)
Gross weight: 905 lb (411 kg) 135 lbs of Water Ballast
PerformanceMaximum glide ratio: 34:1
Wing loading: 7.25 lb/sq ft (35.4 kg/m2)