Schleicher K7

K7 Rhönadler
Role	Glider
National origin	West Germany
Manufacturer	Alexander Schleicher GmbH & Co
Designer	Rudolf Kaiser
Introduction	1960
Status	Production completed
Number built	550
Developed from	Schleicher Ka-2
Variants	Schleicher ASK 13

The Schleicher K7 Rhönadler 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

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After 550 had been built, the K7 was superseded in production by the Schleicher ASK 13.^[1]^[2]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

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]

A K7 was assigned to 2 Wing AAFC and used to train Australian Air Force Cadets 228 Squadron at Bundaberg from 2007 to 2014.^[5]

Variants

Ka-2: 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^[1]

Specifications (K7)

Data from Sailplane Directory, Soaring and FAA Type Certificate 7g3,^[1]^[2]^[3] and The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde^[6]

General characteristics

Crew: one
Capacity: one passenger
Length: 8.15 m (26 ft 9 in)
Wingspan: 16.0 m (52 ft 6 in)
Wing area: 17.56 m² (189.0 sq ft)
Aspect ratio: 14.6:1
Airfoil: root: Goettingen 533 (16%), mid: Goettingen 533 (14%), tip: Goettingen 533 (14%)
Empty weight: 282 kg (622 lb)
Max takeoff weight: 484.5 kg (1,068 lb)

Performance

Stall speed: 59 km/h (37 mph, 32 kn)
Never exceed speed: 200 km/h (120 mph, 110 kn)
Rough air speed max: 130 km/h (81 mph; 70 kn)
Aerotow speed: 130 km/h (81 mph; 70 kn)
Winch launch speed: 100 km/h (62 mph; 54 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/m² (5.60 lb/sq ft)

Notes

^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k Activate Media (2006). "Ka-7 Schleicher". Archived from the original on 17 November 2011. Retrieved 23 July 2011.
^ ^a ^b ^c ^d ^e ^f ^g ^h Said, Bob (November 1983). "1983 Sailplane Directory". Soaring Magazine. Soaring Society of America. USPS 499-920.
^ ^a ^b ^c ^d ^e Federal Aviation Administration (February 1961). "Type Certificate Data Sheet No. 7g3" (PDF). Retrieved 23 July 2011.
^ Lednicer, David (2010). "The Incomplete Guide to Airfoil Usage". Retrieved 23 July 2011.
^ "Gliding". 1 January 2018. Retrieved 20 April 2020.
^ Shenstone, B.S.; K.G. Wilkinson; Peter Brooks (1958). The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs dans Le Monde (in English, French, and German) (1st ed.). Zurich: Organisation Scientifique et Technique Internationale du Vol a Voile (OSTIV) and Schweizer Aero-Revue. pp. 9–13.

References

Activate Media (2006). "Ka-7 Schleicher". Archived from the original on 17 November 2011. Retrieved 23 July 2011.
Said, Bob (November 1983). "1983 Sailplane Directory". Soaring Magazine. Soaring Society of America. USPS 499-920.
Federal Aviation Administration (February 1961). "Type Certificate Data Sheet No. 7g3" (PDF). 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 English, 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

Media related to Schleicher K 7 at Wikimedia Commons

[SD-1] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k Activate Media (2006). "Ka-7 Schleicher". Archived from the original on 17 November 2011. Retrieved 23 July 2011.

[SoaringNov83-2] ^ ^a ^b ^c ^d ^e ^f ^g ^h Said, Bob (November 1983). "1983 Sailplane Directory". Soaring Magazine. Soaring Society of America. USPS 499-920.

[7g3-3] Federal Aviation Administration (February 1961). "Type Certificate Data Sheet No. 7g3" (PDF). Retrieved 23 July 2011.

[Incomplete-4] Lednicer, David (2010). "The Incomplete Guide to Airfoil Usage". Retrieved 23 July 2011.

[5] "Gliding". 1 January 2018. Retrieved 20 April 2020.

[Shenstone-6] Shenstone, B.S.; K.G. Wilkinson; Peter Brooks (1958). The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs dans Le Monde (in English, French, and German) (1st ed.). Zurich: Organisation Scientifique et Technique Internationale du Vol a Voile (OSTIV) and Schweizer Aero-Revue. pp. 9–13.

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