Designed by Rudolf Kaiser, the ASK-21 was Schleicher’s entry to the composite two-seat sailplane market, first flew in 1979 and is approved for a number of aerobatic maneuvers. Originally an improved version of the AS-K 13 with glassfibre wings and T-tail was studied but the requirement for a new two-seater was met instead of the AS-K 21. Differing from the AS-K 13 in having a wing span increased to 17m (55ft 9.25in), a T-tail, a more streamlined fuselage, and a non-retractable semi-recessed nose wheel, as well as a sprung fixed monowheel with drum brake and a steel-shod rubber tailskid. A tailwheel was available as an option instead of a skid. The structure is fiberglass and foam wing, fiberglass honeycomb sandwich fuselage and tail. Schempp-Hirth type airbrakes (upper surface only), ailerons and elevators are operated by pushrods in ball bearing; the rudder is cable-operated. Wings attach with a tongue- and- fork connection and two pins.
The cantilever single-spar mid-set wings have Wortmann aerofoil sections and 4° dihedral, and there are Schempp-Hirth air brakes in the upper and lower surfaces. The wing tips are turned down to reduce tip stalling. The tailplane is fixed, with a separate elevator with spring trim. Unlike the ASK13, there are two separate cockpit canopy sections, the front one opening forwards and the rear one rearwards, and the pilots sit in a semi-reclining position, with dual controls.
Production of the AS-K 21 began in 1979 and the prototype first flew in December 1978. A flight test evaluation by Dick Johnson demonstrated a best L/D of 31:1.
The United States Air Force Academy operates 4 ASK-21’s as the TG-9.
Span: 17.9 m / 55 ft 9.25 in Length: 8.35 m / 28 ft 10 in Height: 1.55 m / 5 ft 3 in Wing area: 17.95 sq.m / 193.21 sqft Aspect ratio: 16.1 Airfoil: Wortmann FX-S0 2-196 and FX 60 – 126 Empty weight: 360 kg / 794 lb Gross Weight: 600 kg / 1323 lb Water ballast: None Wing Load: 31 kg/sq.m / 6.34 lb/sq.ft Max speed: 135 kt / 250 km/h Stalling speed: 33 kt / 62 km/h Max aero-tow speed: 96 mph 94 kt / 175 km/h Min sinking speed: 0.65 m/s / 2.13 ft/sec at 42 mph L/DMax: 35 85 kph / 46 kt / 53 mph Best glide ratio: 34:1 at 59 mph Seats: 2
The AS-W20, like the AS-W 19, was designed by Dipl-lng Gerhard Waibel and is a 15m Unrestricted Class version of the AS-W 19 fitted with camber changing flaps to take advantage of the new March 1975 CIVV regulations for this class of sailplane. It has an additional high drag range of flap movement incorporating a special mechanism to eliminate pitch and airspeed changes when the flap position is changed between 30° and 55°. The AS-W 20 also has a new device, developed by Wil Schuemann, that automatically co-ordinates and optimises the flap position to the prevailing airspeed so as to give optimum glide performance and to reduce the pilot’s workload. This device also eliminates the need for underwing air brakes, although the AS-W 20 has larger spoilers in the wing upper surfaces than the AS-W 19.
Apart from its flaps, the AS-W 20 is very similar to the AS-W 19, with longer ailerons of narrower chord, which rise to -8° when the flaps are lowered to 55° for landing, and with the same glassfibre sandwich construction and T-tail; up to 265lb of water ballast can be carried, and the cockpit canopy hinges to open upward like the AS-W 19’s.
The fiberglass ASW-20 prototype first flew on 29 January 1977 and was a success, winning numerous world and national championships. Built for the 15 m racing class, it features trailing edge flaps which interconnect with the ailerons and allow the entire trailing edge to operate as a flap between -9 and +5 degrees. The flaps also act as ailerons, but deflect only half of the aileron amount. The fuselage is similar to that of the ASW-19. Schempp-Hirth type airbrakes are provided on the upper wing surface only and operate in conjunction with the flaps at approach setting.
The -20B model was introduced in 1983 incorporating new aerodynamic developments in the form of pneumatic jets (about 860) placed in the lower wing surface, drawing impact air from pitot inlets and exhausting it into the boundary layer to delay underwing flow separation. The B model has its gross weight increased to 525 kg / 1,157 lb. Other changes include automatic elevator hookup, an instrument cluster attached to the forward-hinged canopy, and a hydraulic disc brake.
Schleicher ASW 20 ZK-GLD
The -20C model has a slightly modified cockpit, an maximum gross weight of 454 kg / 1,001 lb and water ballast of 120 kg / 264 lb.
Schleicher also introduced an ASW-20L variant (the L denoting Lang, or long), with span extended to 16.59 m (54ft 1.5in) by use of detachable tip extensions, making the ASW- 20L, -20BL and 20CL for Open Class competition. 48 of this variant had been built by the beginning of 1980. In these, water ballast is restricted to 50 kg / 110 lb and gross weight is 430 kg / 948 lb (BL) and 380 kg / 837 lb and no ballast (CL). With the extended tips, best glide ratio goes up to about 46.
The Schleicher ASW 20-L is a high performance single-seat competition glider of all-composite construction with a mid-wing layout and T-tail. The L version indicates optional extended wing tips from 15 to 16.59 metres. The glider’s flight controls consist of a cable operated rudder and push-pull rods for the elevator, ailerons, flaps and the upper wing surface airbrakes. The flap system incorporates a mechanical mixing unit that provides partial flap movement to augment aileron control when the control stick is moved laterally. In addition, the flaps have five selectable positions that are designed to maximise laminar flow over a variety of speed ranges. The flap positions that provide the low drag performance are position one to four. Flap five is a high drag configuration and used for landing.
The range of speeds to fly, at particular flap positions and various wing loadings are provided in the Flight Manual. For example, flap position four is recommended when thermalling. At a wing loading of 1.3g, (40 degrees angle of bank), the best low drag speeds are between 49 and 55 kts. The Flight Manual also provides minimum speeds to fly for the various flap configurations. At 454 kg MAUW, in a wings level attitude at flap position four, the recommended minimum speed is 43 kts. It is claimed the glider spins easier and flatter in the Flap 4 and 5 configurations than with negative (up) flap settings. The explanation goes on further to point out that negative flap should be used to prevent wing drops and spins but recognises that this is impossible when thermalling at low level. In that regard, the Flight Manual recommends the use of safety speeds in excess of the minimum recommended. For spin recovery, the Flight Manual includes a recommended recovery technique and some additional remarks: ‘(1) Apply opposite rudder, i.e. against the direction of rotation of the spin. (2) Short pause. (3) Ease the control column forward, until the rotation ceases and sound airflow is established again. (4) Centralise rudder and allow sailplane to dive out. Recovery from spin can be easier achieved if the flaps are set in negative position. Extending the airbrakes slows down rotational speed but needs more height for recovery and therefor is less recommended. If the Schleicher ASW 20 recovers itself from a spin, it starts a spiral like side-slip with high increase in speed. Recovery from this flight attitude is done by usual control inputs. At forward C. of G. positions the ASW 20 -L spins very steeply and starts a spiral dive in less than one turn, whereas at rear C. of G. positions the gliders pitch becomes steeper and steeper after an initial flat and slow turn (approximately 30 degrees negative pitch) until the transition into a spiral-dive develops after five to seven turns.’
The ASW-20 was also license built by Centrair in France in three variants. The ASW-20F and ASW-20FL are the Centrair equivalents to the 20 B and 20BL model while the 20 FP is an F model with NASA winglets designed to improve performance in weak conditions. The Centrair ASW 20F is said to have improved water ballast and wheel brake systems, as well as a better cockpit finish. This received its French certification on 31 March 1978.
Two AS-W 20s at the 1981 World Gliding Championships were fitted with winglets for improved performance. ASW-20’s won 2nd and 3rd places in the 15 m class at the 1983 World Championships at Hobbs, NM. Roy Mcmaster, Karl Striedeck and John Seymour won jointly, with others, the world triangle distance record of 1,435 km / 891.6 miles in 1994 in an ASW-20B.
No. of aircraft built to 6/30/81 365. 1982 Standard price $22,500.
ASW-20 Span: 49 ft 2.5 in / 15.0 m Length: 22 ft 4.5 in / 6.82 m Height: 4 ft 9 in / 1.45 m Wing area: 113.0 sq.ft / 10.5 sq.m Wing section: Wortmann FX-62K-131 Aspect ratio: 21.43 Empty weight: 551 lb / 250 kg Max weight: 1,000 lb / 454 kg Max speed: 168 mph (in smooth air) Max useful load: 450 b Water ballast: 265 lb / 120 kg Max wing loading: 8.85 lb/sq.ft / 43.2 kg/sq.m Max speed: 146 kt / 270 km/h Max aero-tow speed: 112 mph Min sinking speed: 1.97 ft/sec / 0.60 m/sec at 45.5 mph 39 kt / 73 km/h Stall speed: 35 kt / 65 km/h Rough air airspeed: 97 kt / 180 km/h Best glide ratio: 43:1 at 62 mph Glide ratio (L/D): 42:1 at 54 kt / 100 km/h Seats: 1
Designed by Gerhard Waibel, the fiberglass ASW-19 superseded the ASW-15B as Schleicher’s Standard Class Sailpane using a thinner airfoil and a T tail assembly. The ASW 19 was designed to take advantage of the new Standard Class and 15m Unrestricted Class rules of 1975, which now permit camber-changing flaps and water ballast.
The cantilever laminar flow mid-wings are of glassfibre/foam sandwich construction, with a glassfibre roving main spar and Schempp-Hirth metal air brakes above and below each wing. Up to 220lb of water ballast can be carried. The tail unit is also of glassfibre/foam sandwich and the tailplane is an all-moving surface; the AS-W 19B has a tailplane and elevator, and air brakes on the upper wing only. The fuselage is a glassfibre/honeycomb sandwich structure with a reinforced keel, and the nose tapers to a point like that of the AS-W 17. There is a retractable monowheel with an internal drum brake and a tailskid.
The pilot sits in a semi-reclining seat under a large flush-fitting one-piece canopy which hinges at its front end to open upwards. The AS-W 19 Club is a club class version with a fixed unsprung monowheel, no water ballast carried and larger air brakes.
The AS-W 19 first flew in prototype form on 23 November 1975, and production began in the spring of 1976. No. of aircraft built to 6/30/81 319. 1982 Standard price: $19,500.
Bear Selen of the Netherlands won the Standard Class at the 1978 World Championships at Chateauroux in France flying an ASW-19.
The Royal Air Force used 5 ASW-19’s (known as the Valiant T. Mk.1) in its Air Cadet training program.
ASW-19 Span: 15.0 m / 49 ft 2.5 in Length: 6.8 m / 22 ft 3 3/4 in Height: 1.42 m / 4 ft 8 in Wing area: 10.86 sq.m / 118.4 sq.ft Aspect ratio: 20.4 Airfoil: Wortmann FX 61-163/ FX 60-126 Empty weight: 250 kg / 551 lb Gross Weight: 450 kg / 994 lb Payload: 200 kg / 442 lb Water ballast: 100 kg / 220 lb Wing Load: 41.06 kg/sq.m / 8.47 lb/sq.ft Max speed: 152 mph / 138 kt / 255 km/h Max aero-tow speed: 109 mph Max rough air speed: 132 kt / 245 km/h Stalling speed: 36 kt / 67 km/h Min sinking speed: 0.62 m/s / 2.30 ft/sec / 1.20 kt at 53 mph / 39 kt / 72 km/h Best glide ratio: 38.5:1 at 67 mph / 60 kt / 110 km/h Seats: 1
ASW19B Seats: 1 Length: 22 ft Height: 5 ft Wingspan: 49 ft Wing area: 118.4 sq.ft Wing aspect ration: 20.4 Max wt: 1000 lb Standard empty wt: 540 lb Max useful load: 460 lb Water ballast: 220 lb Wing loading: 8.4 lbs/sq.ft Min sink: 122 fpm @ 39 kt Max speed: 138 kt Stall speed: 35 kt Glide ratio: 39-1 @ 51 kt Rough air airspeed: 95 kt
Designed by Rudolf Kaiser, this single-seater Club Class sailplane was intended as a type on which pilots can progress from the first solo stage to their early competition flights, and is based on the earlier and popular Ka 6E and Ka 8, embodying the docile handling characteristics, simple and rugged construction, soaring ability in weak thermals and good cross-country performance of these types.
The single spar wooden wing has the same aerofoil section as the Ka 6E and a very similar plan form; there are Schempp-Hirth air brakes above and below the wing, the rear part of which is fabric-covered and the ailerons are plywood-covered. The cantilever wooden tail unit has a ply-covered fin and tailplane and fabric-covered rudder and elevators; there is a Flettner trim tab in the elevator. The fuselage, like that of the Ka 8B, is a welded steel tube framework with spruce longerons, and covered overall with fabric; the nose portion is of glassfibre. The pilot sits in a semi-reclining position under a hinged one-piece blown Plexiglas canopy that gives excellent all-round visibility. There is a fixed monowheel just ahead of the c of g with an internal brake, together with a sprung tailskid, and there is no nose skid.
Of similar basically all-wood construction to the Ka 6E and Ka 8, the AS-K 18 first flew in prototype form in October 1974.
No. Built: 48
Schleicher AS-K 18 Wing span: 16 m / 52 ft 5.75 in Wing area: 12.99 sq.m / 139.8 sqft Aspect ratio: 19.71 Airfoil: NACA63618/Joukowsky 12% Length: 22 ft 11.5 in / 7.0 m Height: 5 ft 6 in / 1.68 m Empty Weight: 215 kg / 474 lb Gross Weight: 335 kg / 739 lb Water ballast: None Max wing loading: 23.0 kg/sq.m / 4.71 Ib/sq.ft Max speed: 124 mph / 108 kt / 200 km/h Max rough air speed: 108 kt / 200 km/h Stalling speed: 32.5 kt / 60 km/h L/DMax: 33 at 75 kph / 46.5 mph / 40.5 kt MinSink: 0.62 m/s / 2 ft/sec at 70 kph / 40.5 mph / 35 kt Seats: 1
Also known as the Super Orchidee, this Open Class high performance single-seater was designed by Dipl-lng Gerhard Waibel as a development of the AS-W 12. It was the second of Waibel’s Open Class designs.
Superseding the ASW-12, it is a shoulder wing monoplane with a 90 metre wingspan which is in four sections, only 4.5 inches deep at the root. It has a fibreglass span skin, while the fuselage is monocoque two-skin glass fibre sandwich of a special plastic hexcell monocoque. It is dominated by the large dorsal fin and rudder, which is over 6 ft high, which is sculptured from a 6 inch diameter fuselage where the empennage (conventional low-set tailplane and elevator) emerges. The mainplanes have full length four-position flap/ ailerons which give a variable wing geometry of from +9 deg to –11 deg.
The modified Wortmann wing section is thicker than the AS-W 12’s to enable water ballast to be carried in wing tanks. Built in the wings forward of the spar are rubberised ballast tanks with a capacity of 95 litres / 100 kg / 220 lb. For penetration, this load can be dumped in 1 min 50 secs. The aluminum double segment dive brakes in both the upper and lower surfaces are effective to the extent that the tail parachute used in the prototype is no longer a standard item. The single, retractable sprung mono landing wheel is a large 500 x 15, with considerable ground clearance. The wheel brake is operated by a T-bar alongside the left leg. Cockpit space is ample and lengthy, and a pilot up to 6 ft 6 ins can be accommodated quite easily in a semi-reclining seat under a flush-fitting one-piece canopy. Controls are conventional. Ventilation is drawn from the fuselage near the trailing edge. Visibility is excellent, comfort good, and all control reaches are very good.
It first flew in prototype form on 17 July 1971 and 52 AS-W 17s had been built by January 1977; production has now ceased.
1972 Schleicher ASW 17
The AS-W 17 soon made its mark in competition flying, coming second in the Open Class in the 1972 World Championships at Vrsac, Yugoslavia, flown by Mathias Wiitanen of Finland, third in the 1974 World Championships at Waikerie, Australia, flown by Hans-Werner Grosse of Germany, and winning the 1976 World Championships, held in Finland, for Britain flown by George Lee; this was the first British victory since 1952. The AS-W 17 has made some notable long distance flights, inlcuding a world record goal flight of 765.4 miles by Hans-Werner Grosse on 16 April 1974; he also set a triangular distance record of 660.5 miles (1,063km) in Australia in an AS-W 17 on 18 January 1977, this flight also breaking the speed record for a 1,000km triangular closed circuit at 61.2mph. An ASW-17 flown by Hans Werner Grosse of Germany gained the World record 1,000 km speed triangle at 145.33 kph/ 78.5 kt/ 90 mph and the 1,250 speed triangle at 133.24 kph/ 71.9 kt/ 82.8 mph in 1980.
ASW-17 Wing span: 20m / 65 ft 7.5 in Wing area: 14.86 sq.m / 159.8 sq.ft Wing section Wortmann FX-62-K-131 (modified) Aspect ratio: 27 Length: 24 ft 9.25 in / 7.55 m Height: 6 ft 1.25 in / 1.86 m Empty Weight: 404 kg / 890 lb Payload: 166 kg / 367 lb Gross Weight: 570 kg / 1257 lb Water ballast: 100 kg / 220 lb Max airspeed: 130 kt / 149 mph / 240 km/h (in smooth air) Rough air speed: 130 kt / 240 km/h Stall: 37 kt / 68 km/h L/DMax: 100 kph / 54 kt / 62 mph at 42 kt MinSink: 0.50 m/s / 1.64 fps / 0.97 kt at 46.5 mph / 40.5 kt / 75 km/h Best glide ratio: 48.5:1 at 65 mph / 56.5 kt / 105 km/h Wing Load: 38.36kg/sq.m / 7.8lb/sq.ft Water ballast: 220 lb Seats: 1
The AS-K 16 is a side-by-side two-seater motor glider, with dual controls. The type is of mixed construction with a welded steel tube fuselage covered in fabric, plywood and glassfibre. The cantilever single-spar low-set wooden wings are fabric-covered with glassfibre tips and spoilers in the upper surfaces. The tail unit is of wooden construction with fabric covering, with combined trim and anti-balance tabs in the port elevator. The AS-K 16 has main wheels retracting inwards into the bottom of the fuselage, and a fixed tailwheel; the main wheels have rubber shock absorbers and Tost drum brakes. The pilots sit under a one-piece blown canopy that hinges sideways to open. Powerplant is a 72hp Limbach SL 1700EB1 modified Volkswagen ‘flat four’ engine driving a Hoffman HO-V 62 two blade variable-pitch propeller.
It first flew in prototype form on 2 February 1971 and first appeared in public at the second German Motor Glider Competition at Burg Feuerstein in June that year, but it did not compete.
An AS-K 16 flown by Hans Werner Grosse and Ing R. Kaiser took third place in the First International Motor Glider Competition in 1974.
By January 1976 38 AS-K 16s had been built, but it is now out of production.
Engine: VW Limbach, 75 hp Wingspan 49 ft 2 in Length 21 ft 10 in Gross 1,540 lb Empty 1,010 lb Useful 530 lb Fuel 60 lb Wing loading 7.1 lbs/sq ft Wing aspect ratio 17.1 Max airspeed 110 kt Rough air speed 110 kt Stall 40 kt Lift to drag 25 at 50 kt Sink 3 fps at 45 kt Wingspan 53 ft Length 24 ft Seats 2
Engine: Limbach SL 1700 EB1, 53.7 kW (72 hp) Span: 52 ft 6 in / 16.0 m Length: 24 ft 0.25 in / 7.32 m Height: 6 ft 10.75 in / 2.10 m Wing area: 204.5 sq ft / 19.0 sq.m Aspect ratio: 13.5 Wing section: NACA 63618/Joukowsky 12% Empty weight: 1,036 lb / 470 kg Max weight: 1,543 lb / 700 kg Water ballast: None Max wing loading: 37.0 kg/sq.m / 7.57 lb/sq ft) Max speed: 124 mph / 108 kt / 200 km/h Stalling speed: 37 kt / 69 km/h Min sinking speed: 3.28 ft/sec / 1.0 m/sec at 46 mph / 40 kt / 74 km/h Best glide ratio: 25:1 at 58.5 mph / 51 kt / 94 km/h Take-off run: 755 ft / 230 m Rate of climb at S/L: 150 m/min / 492 ft/min Range: 310 miles / 500 km / 270 nm
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.
This single-seater motor glider was originally known as the Ka 12 and was designed by Ing Rudolf Kaiser but, to avoid confusion with the AS-W 12 high performance sailplane which was also built by Schleicher, it was redesignated AS-K 14.
Of conventional wooden construction, it has what is basically a Ka 6E’s semimonocoque fuselage with plywood covering married to low-set cantilever wood and fabric wings with 5° dihedral, similar to the Ka 6E’s and with the same aerofoil section; the single-spar wings have spoilers in the upper surfaces and plywood-covered ailerons. The pilot sits under a large one-piece blown Plexiglas canopy that hinges sideways to starboard, and the landing gear consists of a manually retracted monowheel on a leg tall enough to give adequate ground clearance for the propeller, plus a tailskid. Powerplant is a 26hp Hirth F10 K19 ‘flat four’ two-stroke engine in a conventional tractor installation driving a two-blade Hoffman feathering propeller; starting is manually. The tail unit is of wood/plywood/fabric construction, with a low-set all-moving tailplane.
The prototype made its first flight on 25 April 1967, and the type took second, third and fourth palces in the first at Burg Feuerstein in the German Motor Glider Competition, which was held in 1970; in the sixth of these competitions, in 1976, the AS-K 14 was still good enough to take second and third places.
This tandem two-seater training and high performance glider was developed from the earlier Ka 7, likewise designed by Rudolf Kaiser, and has similar swept forward single-spar wooden wings in the mid-set instead of high position, this lowering of the wings allowing a larger one-piece blown Mecaplex canopy, hinged to starboard, to be fitted giving better all-round visibility; other improvements over the Ka 7 include more comfortable seating, while the AS-K 13 has a better performance than the Ka 7.
AS-K 13 ZK-GKA
There are metal Schempp-Hirth air brakes above and below the wing, and the wooden ailerons are fabric-covered. The wings have a forward sweep of 6° at the quarter-chord line and 5° of dihedral; the D-type leading edge torsion box is of plywood and the whole wing is fabric-covered. The fuselage is a welded steel tube structure with spruce stringers and fabric-covered overall, except for the nose, which is of glassfibre; the turtle decking aft of the cockpit canopy is a plywood shell. The cantilever wooden tail unit is plywood-covered, except for the rear part of the rudder and elevators, which are fabric-covered, and there is a Flettner trim tab in the starboard elevator. In later models, a nosewheel was substituted for the skid. Landing gear consists of a non-retractable sprung monowheel with a drum brake, mounted aft of the cg, with a skid under the forward fuselage and a steel tailskid. The pilots have glassfibre seat panels for greater comfort, and adjustable rudder pedals; there is provision for radio and oxygen, and an aero-tow release is fitted in the nose.
It first flew in prototype form in July 1966 and by January 1978 a total of approximately 700 AS-K 13s had been built, with production continuing. The type is also sold in kit form for amateur constructors.
After Schleicher ceased production, the sailplane has been license-built by Jubi GmbH of Oerlinghausen, Germany.
This Open Class single-seater was designed by Gerhard Waibel – hence the ‘W in its designation -as a production development of the Akaflieg Darmstadt D-36 Circe, in the design of which Waibel had also participated, and which had won the 1964 German National championships.
Of glassfibre reinforced plastic/balsa sandwich construction, the AS-W 12 has cantilever shoulder wings of high aspect ratio (25.8) and with full-span camber-changing flaps interconnected with the ailerons. There are no air brakes, and early examples lacked the later added (and at first non- jettisonable) tail chute. The monocoque fuselage is similar in outline to that of the D-36 Circe, and the pilot sits in a semi-reclining position under a long flush-fitting two-piece cockpit canopy. Landing gear consists of a large retractable unsprung monowheel with brake, plus a tailskid, and a small fixed-incidence tailplane and elevators are mounted on top of the fin.
The prototype AS-W 12 was built by Edgar Krȁmer, who made the first flight in it on 31 December 1965, and the type has since achieved a number of important competition victories and record-breaking flights. In 1969 W. Scott of the USA set a new world goal flight record of 600 miles in an AS-W 12, and in 1970 Hans-Werner Grosse of West Germany became one of the few pilots to make a flight of 1,000km (621 miles), also in an AS-W 12; on 25 April 1972 he set a world record for distance in a straight line by flying 907.7 miles. Grosse was also runner up in the Open Class of the 1970 World Championships at Marfa, Texas, in which five of the first nine places in this class were taken by AS-W 12s.
One example belongs to the National Soaring Museum. No. Built: 15
Wing span: 18.3 m / 60 ft 0.5 in Length: 7.35 m / 24 ft 1.5 in Height: 5 ft 3.75 in Wing area: 13.0 sq.m / 140 sq.ft Aspect ratio: 25.8 Airfoil: Wortmann FX 62-131K mod. Empty Weight: 290 kg / 640 lb Payload: 140 kg / 308 lb Gross Weight: 430 kg / 948 lb Water ballast: None Max speed: 124 mph / 108 kt / 200 km/h Max rough air speed: 54 kt / 100 km/h Stalling speed: 35 kt / 65 km/h L/DMax: 47 at 105 kph / 56 kt / 65 mph MinSink: 0.49 m/s / 1.6 fps / 0.95 kt at 45 mph / 39 kt / 72 km/h Wing Load: 33.06 kg/sq.m / 6.07 lb/sq.ft Seats: 1
