Schleicher ASW 15
This high performance Standard Class single-seater was designed by Dipl-lng Gerhard Waibel, and is of glassfibre/foam sandwich construction, it has an all-moving horizontal tail and metal airbrakes for glidepath control.
The AS-W 15 resembles the AS-W 12 externally except for an allmoving tailplane set low on the fin, and the cantilever shoulder wings have a glassfibre roving spar and a glassfibre/balsa sandwich torsion box; the Schempp-Hirth air brakes are spring-sealed in separate boxes to preserve the streamlining, and the ailerons are of glassfibre/foam sandwich construction.
The fuselage is a glassfibre/honeycomb sandwich structure, and ease of rigging is ensured by using tongue-fork connections for the wings, secured by two bolts. The tailplane is similar in construction to the wing, while the fin is similar structurally to the fuselage and the rudder has the same structure as the ailerons. The monowheel is retracted manually by means of push-pull rods, and has an internal drum brake. The pilot sits in a semi-reclining seat under a large flush-fitting one-piece canopy, and his rudder pedals are adjustable in flight.
The ASW-15 was Schleicher’s first composite Standard Class design, originally appearing with a fixed wheel and no water ballast in conformity with the then Standard Class rules. It first flew in prototype form in April 1968, and initially had a fixed monowheel and fairing which could be converted into a retractable one for Open Class competitions, but after this requirement was relaxed the retractable wheel became standard.
With the modification of the Standard Class rules to allow water ballast and retractable gear the ASW15B introduced a number of improvements, including a larger monowheel, a strengthened fuselage keel, a larger rudder, a lengthened cockpit and - as an optional 'extra' - two 40 litre (38 kg / 83 lb) water ballast tanks; the all-up weight was increased.
The type made its competition debut at the 1968 World Championships at Leszno in Poland, when an AS-W 15 flown by Hans-Werner Grosse of Germany came 10th in the Standard Class.
A total of 447 AS-W 15s of all versions had been built by January 1977, and production has now ended.
In 1976 an AS-W 15B was fitted with a 30hp Wankel KM 27 300cc rotating piston engine by Ing Joseph Vonderau of Fichtel & Sachs System- Technik. In this form it was known as the AS-W 15M, and a 4.4 Imp gallon fuel tank was installed.
Wing span: 15m / 49 ft 2.5 in
Wing area: 10.68 sq.m / 118.2 sq.ft
Length: 21 ft 3 in
Height: 4 ft 9 in
Empty Weight: 230 kg / 507 lb
Payload: 178 kg / 393 lb
Gross Weight: 408 kg / 900 lb
Water Ballast: 0
Max speed: 136.7 mph
Max aero-tow speed: 90 mph
L/DMax: 38 at 89 kph / 48 kt / 55 mph
MinSink: 0.55 m/s / 1.8 fps / 1.46 kt at 45.5mph
Wing Load: 37.11kg/sq.m / 7.61lb/sq.ft
Aspect ratio: 20.45
Airfoil: FX 61-163, FX 60-126