M.Hardy. Gliders & Sailplanes of the world

Akaflieg Darmstadt D-36 Circe

  The Akademische Fliegergruppe of Darmstadt Technical High School has been involved in designing, building and flying gliders since as far back as 1909, and among its more successful designs were the Edith of ДальшеMore>>> 1922, the Konsul, which was the first 18m (59ft 0 1/2 in) span glider, and the metal high-performance D-30 Cirrus, which had an unusual pod-and-boom type fuselage and a minimum sinking speed of only 1.6ft/sec, being among the most efficient of the prewar German designs. After the war came the D-34a high-performance single-seater, which first flew in 1955, followed by the improved D-34b, which first flew in the autumn of 1956, the D-34c, first flown in the spring of 1958, and the D-34d, which made its first flight in March 1961. By this time members of the Akaflieg Darmstadt were investigating the possibilities of new materials such as reinforced glassfibre bonded resins and the D-36 Circe high-performance single-seater, on which design work started in the spring of 1963, made extensive use of these. The first of two D-36s made its first flight in March 1964 and went on to win the German National championships that year. The D-36 also took second place in the 1965 World Championships at South Cerney. The wing torsion box shell is of balsa reinforced with glassfibre and epoxy resin; camber-changing flaps and Schempp-Hirth air brakes are featured, although the second prototype differed from the first only in having these air brakes removed and replaced by a tail braking parachute. The monocoque fuselage is of balsa reinforced with glassfibre and epoxy resin, while the front section of the cockpit canopy is fixed and the rear part removable. The undercarriage consists of a large manually-retracted monowheel forward of the centre of gravity. The T-tail unit is of similar construction to the wings. The D-36 Circe was developed into the Schleicher AS-W 12 for advanced competition and long-distance flying.


Data: D-36
Span: 58 ft 3 1/2 in
Length: 24 ft 1 1/2 in
Height: 4 ft 11 in
Wing area: 137.8 sqft
Aspect ratio: 24
Empty weight: 622 lb
Max weight: 904 lb
Max speed: 124 mph
Min sinking speed: 1.83 ft/sec at 52 mph
Best glide ratio: 44:1 at 58 mph



Akaflieg Darmstadt D-39

  This single-seat motor glider utilises the basic airframe of the D-38 high performance sailplane designed by the Akademische Fliegergruppe of Darmstadt University, which went into production in slightly modified form as the Glaser-Dirks DG-100. The D-39 differs from the D-38 chiefly in having a low-mounted wing with 4° dihedral from the roots, and two 47hp modified Fichtel & Sachs KM-914V engines in the nose coupled to drive a two-blade wood and glassfibre propeller which, when stopped for soaring flight, is folded back against the sides of the nose to eliminate drag. The prototype D-39 made its first flight on 28 June 1979, powered temporarily by a 68hp Limbach SL1700 'flat four' engine. Of similar glassfibre/balsa sandwich construction to the D-38, the D-39 has glassfibre/Klegecel foam sandwich ailerons and Schempp-Hirth air brakes in the upper wing surfaces; no flaps are fitted. The T-tail has an all-moving one-piece swept tailplane, with half-span Flettner tab, and there is a manually-retractable sprung monowheel with a drum brake, plus a small tailwheel. The pilot sits on a semi-reclining seat under a flush-fitting canopy, the rear section of which is detachable for entry and exit.


Span: 49 ft 2 1/2 in
Length: 23 ft 5 1/2 in
Height: 3 ft 4 1/4 in over fuselage
Wing area: 118.4 sqft
Aspect ratio: 20.5
Empty weight: 639 lb
Max weight: 882 lb
Max speed: 155 mph (power off)
Max aero-tow speed: 103 mph
Min sinking speed: 2.30 ft/sec at 52 mph
Best glide ratio: 36:1 at 65 mph
Max rate of climb: 885 ft/min at sea level
Range with max fuel: 310 miles