Photograph:
Weatherly 620B VH-WEK (c/n 1551) at Avalon, VIC in 1992 (David C Eyre)
Country of origin:
United States of America
Description:
Single-seat agricultural monoplane
Power Plant:
One 336 kw (450 hp) Pratt & Whitney R-985-AN-1, -3 or -14 B nine-cylinder air-cooled radial engine
Specifications:
- Wingspan: 14.22 m (46 ft 8 in)
- Length: 8.10 m (26 ft 7 in)
- Height: 2.44 m (8 ft)
- Wing area: 25.73 m² (277 sq ft)
- Max speed: 283 km/h (176 mph)
- Cruising speed at 70% power: 207 km/h (129 mph)
- Stalling speed (empty): 87 km/h (54 mph)
- Stalling speed at 2,269 kg (5,000 lb): 105 km/h (65 mph)
- Rate of climb at sea level: 213 m/min (700 ft/min)
- Service ceiling: 4,572 m (15,000 ft)
- Fuel capacity: 329.6 litres (72.5 Imp gals)
- Empty weight: 1,288 kg (2,840 lb)
- Loaded weight: 1,814 kg (4,000 lb)
- Typical agricultural operating weight: 2,676 kg (5,900 lb)
History:
The 620A was an agricultural aircraft produced by the Weatherly Aviation Co of Lincoln, California, and was one in a series of aircraft produced in small volume by the Company for this role. It was a rugged, versatile monoplane fitted with a 336 kw (450 hp) Pratt & Whitney radial engine driving a three-blade Hartzell propeller, and in size it fitted in between the Cessna 188 and Piper Brave aircraft, and the larger Thrush, Snow and Air Tractor types with radial and turbine engines of 448 kw (600 hp) and more.
Looking similar to other radial engined types, such as the Air Tractor AT-301, the 620A was unusual in having vanes on the wingtips which created a downwash outboard of the wing tips introducing small vortices in the tip area resulting in both a delay in the formation of the trailing vortex, and a decrease in its intensity. Hopper capacity was 1,266 litres (278.5 Imp gals). A night landing system could be installed, consisting of two 600 watt adjustable working lamps, two 250 watt turning lamps, wing-tip strobes, and a 70 amp alternator.
Production continued, the next model being the 620B fitted with a 336 kw (450 hp) Pratt & Whitney R-985 radial engine, and the 620-BTG fitted with a 373 kw (500 shp) Honeywell TPE-331-1 turboprop.
The type was distributed in Australia by Weather-Air Pty Ltd at Moorabbin, VIC and a number have appeared on the Australian register, including: VH-WEA (c/n 1528), a 620A registered to Leafair Pty Ltd in May 1990; VH-WEI (c/n 1553) registered to Weather-Air Pty Ltd of Mentone, VIC in May 1991; VH-NZG (c/n 1522) registered in Western Australia; and VH-WEK (c/n 1551), a 620B registered to Leafair of Moorabbin in October 1992 which crashed whilst fire-bombing on 31 January 1994 at Mt Murray, VIC.
Registration VH-WEI was allotted twice, the first (c/n 1553) being lost in an accident, the registration being allotted again in 1998 to c/n 1654, this machine, a 620B, being registered to Superspread Aviation of Deniliquin, NSW in February 1998.
VH-WEA (c/n 1528) was noted at Bankstown, NSW in 1999 undergoing conversion to parts.