Volmer VJ-24W SunFun
|Role||Motor glider/Ultralight aircraft|
|National origin||United States|
|Developed from||Volmer VJ-23 Swingwing|
|Variants||Delta Sailplane Nomad|
The Volmer VJ-24W SunFun is an American high-wing, strut-braced, single-seat, pod-and-boom motor glider and ultralight aircraft that was designed by Volmer Jensen and provided as plans for amateur construction by his company Volmer Aircraft of Glendale, California.
Design and development
The SunFun started as a foot-launched glider design, the VJ-24, and was developed into a wheeled undercarriage motor glider, the VJ-24W. The VJ-24 was derived from the earlier Volmer VJ-23 Swingwing and differed from that design by replacing the wooden structure with metal and employing a constant chord, strut-braced wing in place of the VJ-23's cantilever, tapered wing.
The aircraft is built from aluminium tubing covered with aircraft fabric. The 36.5 ft (11.1 m) span wing is braced by V-struts, supported by triangular jury struts. The fuselage is built around a keel tube that mounts the cruciform tail at the aft end, the wing and cockpit in the center and the engine at the front. The specified engines are the Yamaha KT100 15 hp (11 kW) go-kart powerplant and the 10 hp (7 kW) McCulloch MAC-101, mounted in tractor configuration on the front of the keel tube, above the aircraft's nose. The landing gear is of conventional configuration, using spoked bicycle wheels for the main gear. Pilot weight is limited to 200 lb (91 kg).
The take-off and landing distances with the 15 hp (11 kW) engine are both 100 ft (30 m).
- Unpowered three axis-controlled hang glider version, foot launched and landed. Glide ratio is 9:1 at 20 mph (32 km/h) and minimum sink is 180 fpm.
- Powered version with wheeled landing gear.
- Crew: one
- Length: 18 ft 6 in (5.64 m)
- Wingspan: 36 ft 6 in (11.13 m)
- Height: 5 ft 7 in (1.70 m)
- Wing area: 163 sq ft (15.1 m2)
- Empty weight: 165 lb (75 kg)
- Gross weight: 345 lb (156 kg)
- Fuel capacity: 1 US gallon (3.8 l; 0.83 imp gal)
- Propellers: 2-bladed wooden fixed pitch
- Maximum speed: 42 mph (68 km/h, 36 kn)
- Cruise speed: 28 mph (45 km/h, 24 kn)
- Stall speed: 15 mph (24 km/h, 13 kn)
- Range: 30 mi (48 km, 26 nmi)
- Maximum glide ratio: 9:1
- Rate of climb: 350 ft/min (1.8 m/s)
- Rate of sink: 180 ft/min (0.91 m/s)
- Purdy, Don: AeroCrafter - Homebuilt Aircraft Sourcebook, page 315. BAI Communications, July 1998. ISBN 0-9636409-4-1
- Vintage Ultralight Museum (n.d.). "Sun Fun VJ-24W". Retrieved September 29, 2011.
- Rogers, Bennett: 1974 Sailplane Directory, Soaring Magazine, page 100. Soaring Society of America, August 1974. USPS 499-920
- Cliche, Andre: Ultralight Aircraft Shopper's Guide 8th Edition, page E-43. Cybair Limited Publishing, 2001. ISBN 0-9680628-1-4