Yeoman Cropmaster
From Wikipedia, the free encyclopedia
| Yeoman Cropmaster YA-1 | |
|---|---|
| Type | agricultural aircraft |
| Manufacturer | Yeoman Aviation |
| Designed by | C. W. (Bill) Smith |
| Maiden flight | 1960 |
| Introduced | 1960 |
| Status | One aircraft registered in NZ |
| Produced | 1960-1966 |
| Number built | 21 |
| Unit cost | £19,900 |
| Variants | CAC Wackett |
The Yeoman Cropmaster was an Australian agricultural aircraft developed from the CAC Wackett trainer of World War II.
Contents |
[edit] Design and development
The type was developed by Yeoman Aviation, a company set up by Kingsford Smith Aviation Services Pty. Ltd. (KSA) to engage in agricultural aircraft production. KSA had obtained a number of Wacketts following the type's retirement from Royal Australian Air Force service and had converted several for agricultural use as KS-3 Cropmasters. The conversion involved little more than the installation of a hopper located in the rear cockpit of the Wackett.
By contrast the YA-1 Cropmaster involved major modifications to the Wackett airframe. The Wackett fuselage structure of steel tube was retained but had a 23 cubic ft. (650 litre) capacity hopper in lieu of the Wackett's rear cockpit and different external panels of metal and fibreglass (the Wackett fuselage was fabric covered); the Wackett's wooden wing was replaced by a new metal wing. The first two aircraft retained the Wackett's wooden tail, but subsequent aircraft had a metal tail that featured a swept-back fin and larger rudder. The Wackett's fixed tailwheel undercarriage was retained. The Warner Scarab radial engine of the Wackett was replaced by a horizontally-opposed engine, the YA-1 250 being fitted with a Lycoming O-540 engine of 250hp driving a Hartzell propeller, while the YA-1 250R was fitted with a Continental IO-470 also developing 250hp, driving a Hartzell or McCauley propeller.
The first Cropmaster, a YA-1 250, took to the air for the first time in early 1960 (sources disagree on whether it was in January or February). Twenty further aircraft were converted at Bankstown Airport before production ceased in 1966, by which time the company was known as Cropmaster Aircraft. Like it's contemporary the CAC Ceres the Cropmaster was unable to compete with more modern types of agricultural aircraft. Six of the twenty-one aircraft were the YA-1 250R model and the final three aircraft produced featured relocated main landing gear to counteract a tendency for the type to nose over on the ground. Six Cropmasters were exported to New Zealand where one example is still on the civil aircraft register. Several other Cropmasters reportedly still exist in Australia and New Zealand.
An intermediate type was the single Yeoman 175; this had the swept fin of later Cropmasters but retained the Warner Scarab engine. A proposed variant with tricycle undercarriage was the YA-1B, none were built. Another variant was the YA-1 285 with a 285hp Continental engine, sources disagree as to whether any of this variant were produced.
[edit] Specifications (Yeoman YA-1 250R Cropmaster)
General characteristics
- Crew: 1
- Length: 26 ft 4in (8.02 m)
- Wingspan: 35 ft 0 in (10.67 m)
- Height: 9 ft (2.74 m)
- Empty weight: 1,801 lb (817 kg)
- Max takeoff weight: 3,528 lb (1,600 kg)
- Powerplant: 1× Continental IO-470-R horizontally-opposed engine, 250 hp (187 kW)
Performance
- Maximum speed: 133 knots (152 mph, 245 km/h)
- Range: 456 miles (400 nm, 735 km)
- Rate of climb: 900ft/min (4.56m/s)
[edit] References
- Tiger Moth, CT-4, Wackett & Winjeel in Australian Service Stewart Wilson. Aerospace Publications Pty. Ltd. ISBN 1 875671 16 1
- The Observer's Book of Civil Aircraft of Australia and New Zealand Timothy & Elizabeth Hall. Methuen of Australia Pty. Ltd. ISBN 0 454 00075 8
[edit] External links
- http://dbdesignbureau.buckmasterfamily.id.au/aus_aircraft.htm
- http://www.kiwiaircraftimages.com/yeoman.html
[edit] See also
|
||||||||||||||
