The Cosmos Bison, also called the Cosmos Bidulm, is a French two-seat, ultralight trike that is produced by Cosmos ULM. The aircraft is only supplied as a completed aircraft and is not available as a kit.[1]

Bison
Role Ultralight trike
National origin France
Manufacturer Cosmos ULM
Status In production
Variants Cosmos Phase II

Design and development edit

The Bison was designed to comply with the European Fédération Aéronautique Internationale microlight classification. It features a cable-braced hang glider-style high-wing, weight-shift controls, a two-seats-in-tandem open cockpit, tricycle landing gear and a single engine in pusher configuration.[1]

The aircraft wing is made from bolted-together aluminum tubing and covered in Dacron sailcloth. A number of different wings are available for the Bison. The wing is supported by a single tube-type kingpost and uses an "A" frame control bar. Optional equipment includes a cockpit fairing and wheel pants. Engines used are the 37 kW (50 hp) Rotax 503 and 30 kW (40 hp) Rotax 447 twin cylinder, two-stroke powerplants. The landing gear is cable-braced, which allows a folding design for ground transport or storage.[1]

The Bison was later developed into the Cosmos Phase II, by adding larger seats, new landing gear shock absorbers and a redesigned engine mount to reduce vibration. In 2012 the Bison remained in production alongside the Phase II and Phase III, offering a simpler, lighter and less expensive two seater than the newer models.[1]

Specifications (Bison) edit

Data from Bertrand[1]

General characteristics

  • Crew: one
  • Capacity: one passenger
  • Wingspan: 10.6 m (34 ft 9 in)
  • Wing area: 19 m2 (200 sq ft)
  • Empty weight: 123 kg (271 lb)
  • Gross weight: 400 kg (882 lb)
  • Fuel capacity: 40 litres (8.8 imp gal; 11 US gal)
  • Powerplant: 1 × Rotax 447 twin cylinder, air-cooled two-stroke aircraft engine, 30 kW (40 hp)
  • Propellers: 2-bladed wooden

Performance

  • Maximum speed: 85 km/h (53 mph, 46 kn)
  • Cruise speed: 60 km/h (37 mph, 32 kn)
  • Stall speed: 40 km/h (25 mph, 22 kn)
  • Rate of climb: 2.5 m/s (490 ft/min)

References edit

  1. ^ a b c d e Bertrand, Noel; Rene Coulon; et al: World Directory of Leisure Aviation 2003-04, page 97. Pagefast Ltd, Lancaster OK, 2003. ISSN 1368-485X

External links edit