Engineering:Greenwood Witch

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Short description: American ultralight aircraft
Witch
Role Ultralight aircraft
National origin United States
Manufacturer Marvin Greenwood
Designer Marvin Greenwood
Introduction 1982
Status Production completed

The Greenwood Witch is an American ultralight aircraft that was designed and produced by Marvin Greenwood. The aircraft was supplied as a kit for amateur construction.[1][2]

Design and development

The Witch was designed to comply with the US FAR 103 Ultralight Vehicles rules, including the category's maximum empty weight of 254 lb (115 kg). The aircraft has a standard empty weight of 248 lb (112 kg). It features a strut-braced high-wing, T-tail, a single-seat, open cockpit, tricycle landing gear and a single engine in pusher configuration.[1][2]

The aircraft is of mixed construction, including bolted-together aluminum tubing, 4130 steel tubing, wood and dope and aircraft fabric. Its 30 ft (9.1 m) span wing is supported by a single lift strut per side, with jury struts, and incorporates a unique folding mechanism. The wing folds by first hinging the outer panels onto the inner panels and then the whole wing pivots on a central steel post to allow positioning fore-and-aft for towing on its landing gear or for storage.[1]

The Witch accommodates its pilot on an open seat, with a small cockpit fairing with a windshield. The controls are conventional three-axis, with half-span ailerons and an all-flying stabilator. The tricycle landing gear features nose wheel steering and includes a small tail caster. The standard engine supplied was the Zenoah G-25 single cylinder, two-stroke aircraft engine of 22 hp (16 kW). The engine is mounted underneath the center of the wing and drives the pusher propeller though a short extension shaft.[1]

Specifications (Witch)

Data from Cliche and the Virtual Ultralight Museum[1][2]

General characteristics

  • Crew: one
  • Length: 18 ft 2 in (5.54 m)
  • Wingspan: 30 ft (9.1 m)
  • Wing area: 150 sq ft (14 m2)
  • Empty weight: 248 lb (112 kg)
  • Gross weight: 500 lb (227 kg)
  • Fuel capacity: 5 U.S. gallons (19 L; 4.2 imp gal)
  • Powerplant: 1 × Zenoah G-25 single cylinder, two-stroke aircraft engine, 22 hp (16 kW)

Performance

  • Maximum speed: 63 mph (101 km/h, 55 kn)
  • Cruise speed: 50 mph (80 km/h, 43 kn)
  • Stall speed: 26 mph (42 km/h, 23 kn)
  • Service ceiling: 14,000 ft (4,300 m)
  • g limits: +3.8/-2
  • Rate of climb: 500 ft/min (2.5 m/s)
  • Wing loading: 3.33 lb/sq ft (16.3 kg/m2)

See also

Aircraft of comparable role, configuration and era

References

  1. 1.0 1.1 1.2 1.3 1.4 Cliche, Andre: Ultralight Aircraft Shopper's Guide 8th Edition, page E-44. Cybair Limited Publishing, 2001. ISBN:0-9680628-1-4
  2. 2.0 2.1 2.2 Virtual Ultralight Museum (n.d.). "Witch". http://virtualultralightmuseum.com/uz.htm#witch. Retrieved 4 January 2012. 

External links