Photograph:
Ayres S-2R Thrush VH-WBV at Moree, NSW in 1981 (David C Eyre)
Country of origin:
United States of America
Description:
Single-seat agricultural monoplane
Power Plant:
One 895 kw (1,200 hp) Wright R-1820-97 nine-cylinder air-cooled radial engine
Specifications:
- Wingspan: 13.5 m (44 ft 5 in)
- Length: 9.6 m (31 ft 6 in)
- Height: 2.92 m (9 ft 7 in)
- Wing area: 30.35 m² (326.6 sq ft)
- Max speed: 256 km/h (159 mph)
- Cruising speed at 50% power: 249 km/h (155 mph)
- Rate of climb at sea level: 620 m/min (2,033 ft/min)
- Working speed at 30% to 50% power: 161 to 241 km/h (100 to 150 mph)
- Ferry range at 40% power at 225 km/h (140 mph): 1,078 km (670 miles)
- Empty weight: 2,263 kg (4,990 lb)
- Typical operational weight: 4,536 kg (10,000 lb)
History:
In late 1977 the Ayres Corporation of Albany, Georgia, USA purchased the manufacturing and world marketing rights to the Rockwell Thrush Commander 600 and 800 series of agricultural aircraft, and subsequently developed this popular series of aircraft to meet customer requirements, with a range of aircraft available varying in the power plant fitted and the size of the hopper. The basic model was the S-2R-600 with a Pratt & Whitney R-1340 Wasp air-cooled radial engine, this previously being known as the S-2R-1340. This was available in either single or two-seat versions.
The S-2R-1820 was the Bull Thrush, the specifications for which are set out above. This was at the time advertised as ‘The most powerful production ag plane in the world – it’s big…everything about it says muscle – you’re flying with 895 kw (1200 hp) of raw power from the Wright R-1820 engine. Power to get you in and out of those tight places with a full load… power to use short strips on a hot day’. Using rebuilt Wright engines, the Bull Thrush proved a strong, rugged aircraft and has been used for dusting, spreading, fire fighting, etc, for which purpose the extra power of the 895 kw (1,200 hp) engine helped considerably.
The S-2R Turbo Thrush was initially fitted with the Pratt & Whitney Canada PT6A series of engines but a variety of engines was available depending on the requirments of the operator.
Specialty Aircraft Sales of Vancouver, Canada, received Type Approval for the Sea Thrush fitted with Edo floats and a drop-door beneath the hopper, this being aimed at the fire-bombing role. The prototype of the Sea Thrush had a 448 kw (600 hp) R-1340 engine, but production aircraft were to receive the turboprop engine.
The Ayres series of agricultural aircraft has proved very popular in this region with more than 50 examples being registered.