avia.wikisort.org - Glider

The Schneider ES-65 Platypus is a two-seater unflapped glider designed and built by Edmund Schneider Pty in Australia. A single prototype was built, which remains operational as of 2012.

ES-65 Platypus
Role	Two seat advanced trainer Type of aircraft
National origin	Australia
Manufacturer	Edmund Schneider Pty, Adelaide
Designer	Harry Schneider
First flight	August 1984
Number built	1

Design and development

The Edmund Schneider company was originally based in Grunau, Silesia but reformed after World War II in Adelaide, Australia, producing the successful Schneider ES-60 from 1960 until 1970. Anticipating an Australian market for an ES-60-based side by side two-seater Harry Schneider began design and construction of the ES-64, a marriage of ES-60 wings with a new glass reinforced plastic (GRP) fuselage. Australian gliding clubs showed little interest and the project proceeded slowly. In the early 1980s Schneider revived it with a simplified version, the ES-65 Platypus.[1]

The Platypus has the extended plywood skinned ES-60 wing, built around a single spar. The leading edge is unswept but the straight trailing edges have forward sweep that increases on the outer, aileron-carrying, panels. There are airbrakes mounted just aft of the spar on the inner panels. These wings were mid-mounted onto a new GRP fuselage. This has a maximum width of 1.20 m (3 ft 11 in) to accommodate the side by side seating but narrowed in pod and boom style, particularly in plan, behind the wings. The cockpit has a two-piece fixed screen extending almost to the nose and is accessed via a rear hinged, bulged canopy. The pod includes a fixed, faired, centre-line two wheel undercarriage, with a brake-equipped mainwheel under the wings and a smaller nosewheel.[1]

The tail is also mostly GRP, though the elevator uses carbon fibre for lightness. These surfaces are straight-edged and tapering, the fin is tall with a rudder that extends to the bottom of the fuselage. The high aspect ratio horizontal tail surface is mounted midway up the fin.[1]

The Platypus made its first flight in August 1984 and its handling and performance were generally judged to be good. There were plans to produce an all-GRP version, but the funding required was not available and no more ES-65s were built.[1]

Operational history

The prototype, VH-GFA, is owned by a syndicate of members of the Geelong Gliding Club[2] and of the Victorian Motorless Flight Group[3] based at Bacchus Marsh airfield, Victoria. It was still operational in 2005.[1]

Specifications

Data from Sailplanes 1965-2005[1]

General characteristics

• Crew: 2
• Length: 7.726 m (25 ft 4 in)
• Wingspan: 17.70 m (58 ft 1 in)
• Height: 1.7 m (5 ft 7 in)
• Wing area: 16.2 m² (174 sq ft)
• Aspect ratio: 19.3
• Airfoil: Wortmann FX61-164 root, FX61-140 inboard of aileron, FX60-126 tip
• Empty weight: 400 kg (882 lb)
• Gross weight: 590 kg (1,301 lb)

Performance

• Maximum speed: 260 km/h (160 mph, 140 kn)
• Stall speed: 72 km/h (45 mph, 39 kn)
• Never exceed speed: 260 km/h (160 mph, 140 kn)
• Wing loading: 36.4 kg/m² (7.5 lb/sq ft)

References

---