The Sonerai is a small, VW-powered homebuilt aircraft, designed by John Monnett. The Sonerai began to compete as a single-seat, mid-wing, tailwheel Formula-V racer class formed in 1972. The Sonerai soon evolved into a two-seat model called the Sonerai II.
Later versions included a low-wing Sonerai IIL, a tricycle-gear Sonerai IILT and finally the stretched Sonerai IILS and IILTS.
John Monnett came up with the name Sonerai from a combination of the words Sonic and Cosmic-Ray. Many Sonerais have been built and it remains a very popular design for people seeking a low-cost experimental aircraft with good speed and maneuverability. The time to build is between 800 and 1000 hours.
The Sonerai I design and construction started in 1970 with the goal of a flying aircraft to be demonstrated at the 1971 EAA airshow. The aircraft was to meet the new Formula V rules and those of the Professional Race Pilots Association (PRPA) for aircraft powered by 1600cc Volkswagen engines (it will accept VW engines from 1600 to 2800cc displacement).
Inspired by the Spitfire, an elliptical tail profile was incorporated. Elliptical wingtips and a low-wing configuration were dropped, but a low-wing Sonerai II variant was released later. The Sonerai I was designed to use a direct drive 1,600cc VW engine and the Sonerai II was designed to use the 1700cc VW engine.
The wings were designed to fold alongside the fuselage for towing without a trailer and compact storage. The Sonerai II was designed to be soloed from the rear seat. The aircraft is built around a fabric-covered steel-tube fuselage and tail, with all-aluminum wings and a fiberglass cowl.
The aircraft is not available as a kit, and is built using plans, although some parts are available.
Variants:
Sonerai I – single-seat Formula V Racer
Sonerai II – two-seat, mid-wing, conventional gear
Sonerai II-L – two-seat, low-wing, conventional gear
Sonerai II-LT – two-seat, low-wing, conventional gear, tricycle gear developed in 1983
Sonerai II-LS – two-seat, low-wing, stretched fuselage, conventional gear
Sonerai II-LTS – two-seat, low-wing, stretched, tricycle gear
Specifications Sonerai II:
- Crew: 1
- Capacity: 1 passenger
- Length: 18 ft 10 in (5.74 m)
- Wingspan: 18 ft 8 in (5.69 m)
- Height: 5 ft 0 in (1.52 m)
- Wing area: 84.0 sq ft (7.80 m2)
- Airfoil: NACA 64212
- Empty weight: 500 lb (227 kg)
- Max takeoff weight: 1,150 lb (522 kg)
- Fuel capacity: 10 US gal (8.3 imp gal; 38 L)
- Powerplant: 1 × 1700cc modified Volkswagen air-cooled engine air-cooled flat-four, 65–70 hp (48–52 kW)
- Propellers: 2-bladed
- Maximum speed: 140 kn (160 mph, 260 km/h)
- Cruise speed: 120 kn (140 mph, 230 km/h)
- Stall speed: 38 kn (44 mph, 71 km/h)
- Range: 300 nmi (350 mi, 560 km) at 75% power (with reserves)
- Rate of climb: 500 ft/min (2.5 m/s)