Schleicher K7 Rhönadler, aka Ka-7 or K-7, is a West German high-wing, two-seat, glider that was designed by Rudolf Kaiser and produced by Alexander Schleicher GmbH & Co. [1 ] [2 ]
Often referred to as the
Ka-7 or K-7, the US Federal Aviation Administration type certificate officially designates it as the K7. [1 ] [2 ] [3 ]
Design and development [ edit ]
K7 wing being recovered, showing the wooden structure.
The K7 was intended as a two-place
trainer with good performance, a rare combination in trainers of its time. [1 ] [2 ]
The K7 is constructed with a welded steel tube fuselage, covered in doped
aircraft fabric covering. The wing is a wooden structure with a doped fabric covering and employs a Goettingen 533 (16%) airfoil at the wing root, transitioning to a Goettingen 533 (14%) section at the wing tip. The wing features powerful dive brakes. The landing gear is a fixed monowheel. The earlier Ka-2 variant has a plywood monocoque fuselage. [1 ] [2 ] [3 ] [4 ]
After 550 had been built, the K7 was superseded in production by the
Schleicher ASK 13. [1 ] [2 ]
The K7 can be converted into a K7/13 with a conversion kit to lower the wing to the
mid-wing position and installation of a one-piece canopy, rendering the aircraft similar to the ASK-13. [1 ]
Operational history [ edit ]
A K7 was flown to a new world multi-place glider speed record for flight around a 500 km (311 mi) triangle of 84 km/h (52 mph) in 1964 in
South Africa. [1 ] [2 ]
Variants [ edit ]
Early version with a plywood monocoque fuselage
[1 ] [3 ] K7
Main production version with a steel tube fuselage.
[1 ] [2 ] [3 ] K7/13
K7 converted to a mid-wing arrangement, plus a single piece canopy, to resemble an AS-K 13
Specifications (K7) [ edit ]
Data from Sailplane Directory, Soaring and FAA Type Certificate 7g3, [1 ] [2 ] The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde [3 ] [5 ]
Capacity: one passenger
Length: 8.15 m (26 ft 9 in)
Wingspan: 16.0 m (52 ft 6 in)
Wing area: 17.56 m 2 (189.0 sq ft)
Aspect ratio: 14.6:1
root: Goettingen 533 (16%), mid: Goettingen 533 (14%), tip: Goettingen 533 (14%) Airfoil:
Empty weight: 282 kg (622 lb)
Max takeoff weight: 484.5 kg (1,068 lb)
Stall speed: 59.3 km/h (37 mph; 32 kn)
200 km/h (124 mph; 108 kn) Never exceed speed:
Rough air speed max: 130 km/h (80.8 mph; 70.2 kn)
Aerotow speed: 130 km/h (80.8 mph; 70.2 kn)
Winch launch speed: 100 km/h (62.1 mph; 54.0 kn)
g limits: +4 -2
Maximum glide ratio: 26:1 at ~83 km/h (52 mph)
Rate of sink: 0.70 m/s (138 ft/min) at 67 km/h (42 mph)
Wing loading: 27.34 kg/m 2 (5.60 lb/sq ft)
See also [ edit ]
Aircraft of comparable role, configuration and era
References [ edit ]
Activate Media (2006). "Ka-7 Schleicher" . Retrieved 23 July 2011.
Said, Bob (November 1983). "1983 Sailplane Directory". Soaring Magazine (Soaring Society of America). PMID 499-920.
Federal Aviation Administration (February 1961). "Type Certificate Data Sheet No. 7g3" . Retrieved 23 July 2011.
Lednicer, David (2010). "The Incomplete Guide to Airfoil Usage" . Retrieved 23 July 2011.
Shenstone, B.S.; K.G. Wilkinson & Peter Brooks (1958). The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs dans Le Monde (in Primarily English with French and German) (1st ed.). Zurich: Organisation Scientifique et Technique Internationale du Vol a Voile (OSTIV) and Schweizer Aero-Revue. pp. 81–87.
External links [ edit ]
Media related to K 7 at Wikimedia Commons