This object is on display in the Boeing Aviation Hangar room at Steven F. Udvar-Hazy Center in Chantilly, VA.
Collection Item Summary:
Schoolteacher John Monnett designed the Moni (mo-nee) during the early 1980s, and then coined the term 'air recreation vehicle' to describe this airplane. Monnett's design almost captured all the merits that so many leisure pilots longed to find in one aircraft. The Moni looked great just sitting on the ramp. It performed well, and someone reasonably handy with average shop tools could construct one in their own garage. The design had much going for it, but like so many homebuilt aircraft before and since, a few key engineering lapses in the design, plus problems with the engine and propeller, relegated the Moni to the category of homebuilt aircraft that promise much in design but fail to deliver. Harold C. Weston generously donated his Moni to the National Air and Space Museum in April 1992. Weston built the airplane himself and flew it more than 40 hours.
Collection Item Long Description:
Schoolteacher John Monnett designed the Moni (mo-nee) motorglider during the early 1980s and then coined the term 'air recreation vehicle' to describe this airplane. Monnett's design captured many of the characteristics that many leisure pilots longed to find in an aircraft built from a kit. The Moni was an attractive and graceful design. It performed well and anyone reasonably handy with average shop tools could construct one in their own garage. Monnett first flew the Moni during July 1981. He sold about 380 kits from 1982 until his company ceased operations in 1986.
Upon unpacking a mail-order Moni kit, a builder found all components pre-shaped from aircraft-grade aluminum except for the expansive Plexiglas canopy. Only an electric drill, sheet metal shears, and a pop-rivet gun were required to construct most of the aircraft. The wing skins required expertise to bond them to the wing structure but Monnett claimed that overall construction time ran about 350-400 hours.
The finished Moni was a capable of flying basic aerobatic maneuvers such as loops and rolls and a Moni pilot could zip along at 193 km/h (120 mph) or stop the engine and glide around in search of thermal updrafts at a respectable 20:1 glide ratio. Airframe weight totaled about 118 kg (260 lb), a mere 1.8 kg (4 lb) above the legal weight limit for ultralights but the Moni was at least two times faster. This performance depended on a small and economical power plant, the KFM (Komet Flight Motors) 107 two-stroke air-cooled engine that Monnett included with all the kits he sold. This engine was not as reliable as many pilots hoped and several propeller failures occurred, too. Good performance also depended on a sound airframe but glue held the wings together in the early kits. After several wings failed in flight, Monnett redesigned the wings for riveted construction. Some builder/pilots were enthusiastic about the performance. One pilot said, "I think that the Moni is a joy to fly. I have flown throughout Oklahoma, into Texas and Kansas. I took one cross-country that was 700 statute miles [1,127 km] round trip. The Moni does what it was designed to do very well. It is a good day VFR recreational aircraft." Harold C. Weston generously donated his Moni to the National Air and Space Museum in April 1992. Weston built the airplane himself and flew it more than 40 hours.
National Air and Space Museum
Do not reproduce without permission from the Smithsonian Institution, National Air and Space Museum
Gift of Harold C. Weston.
Overall - Aluminum airframe, semi-monocoque construction.
- Wingspan: 8.4 m (27 ft 6 in)
- Length: 4.5 m (14 ft 7.5. in)
- Height: 0.7 m (28 in)
- Weights: Gross, 227 kg (500 lb)
- Empty, 118 kg (260 lb)
- Engine: KFM 107E, two-cylinder, two-stroke air-cooled, 25 horsepower
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National Air and Space Museum Collection
Country of Origin
United States of America
Low-wing, vee-tail motorglider, beige with purple, red, and orange trim; single-seat aircraft built from parts sent to builder by mail-order kit; mounted on roadable trailer with wings detached (A19940029000).