The Schleicher ASK 18 Glider
Designed by Rudolf Kaiser and was the last Schleicher glider to use the traditional construction method, at a time when contemporary aircraft of the same class, such as the Grob G-102 Astir, were made of glass-fibre. The fuselage was derived from the Ka 8 and used welded steel tube and spruce longerons. It is covered in fabric. The wings are from the Ka 6E but with 16-metre span. They have a single wooden spar. The rear part of the wing is fabric-covered and the ailerons are plywood-covered. The tailplane came from the K 10; the fin and tailplane are plywood-covered and the rudder and elevators are fabric covered. A Flettner trim tab is fitted to the elevator. Only the nose cone is glass-fibre. The main-wheel is fixed and has a brake. There is a tail-skid but no nose-skid. The Schempp-Hirth airbrakes extend above and below the wing. First flight was in October 1974.
A variation was the ASK 18B which had a span reduced to 15m. At the end of production in 1977 38 K18s and 9 K18Bs had been built by Schleicher and one unknown variant built from a kit. A further 8 K18-ARs were produced in Argentina.
Length: 6.00 m (19 ft 8 in)
Wingspan: 16.00 m (52 ft 6 in)
Height: 1.68 m (5 ft 6 in)
Wing area: 13.0 m2 (140 ft2)
Aspect ratio: 19.7
Wing profile: Root: NACA 633-618 Mid: NACA 633-614 (with Wortmann leading edge modification)
Empty weight: 215 kg (473 lb)
Gross weight: 335 kg (737 lb)
Maximum speed: 200 km/h (125 mph)
Maximum glide ratio: 34
Rate of sink: 0.62 m/s (122 ft/min)