Auster Workmaster

J/1U Workmaster
J/1U Workmaster at Shobdon airfield, Herefordshire, in April 1987
General information
Type	Agricultural aircraft
Manufacturer	Auster Aircraft Limited
Primary user	Crop Culture (Overseas) Limited
Number built	10
History
Introduction date	1958
First flight	1958
Developed from	Auster Autocrat

The Auster J/1U Workmaster is a late 1950s British single-engined single-seat high-wing agricultural monoplane built by Auster Aircraft Limited at Rearsby, Leicestershire. Of traditional high-wing layout, it carries 90 gallons of spray fluid in a tank beside the pilot, an extra seat being provided for a passenger. The Lycoming 0-360-A engine of 180 h.p. driving a McCauley v.p. propeller giving it ample power; and slotted ailerons and balanced tail controls providing good handling. Oversize tyres were fitted. Take-off run at 2,550 lb gross weight and cruising speed at 65 per cent power are respectively 180 yd and 88 miles per hour (142 km/h). Britten-Norman spray gear was provided by Crop Culture, and this company ordered nine Workmasters.

History

Following the experience of developing the J/1B Aiglet agricultural aircraft, Auster developed a more powerful successor the J/1U Workmaster. Using the basic Autocrat fuselage it was strengthened and had dorsal fin fillets added, low pressure tyres and a 180 hp (134 kW) Avco Lycoming engine.

J/1U Workmaster, built 1958

The aircraft were fitted with Britten-Norman rotary atomizers for crop spraying and a 100 imperial gallon (455 litre) chemical tank in the fuselage. An emergency dump valve allowed the tank to be emptied in 5 seconds. The Workmasters were mainly operated in West Africa, three later returning and are currently (2009) on the U.K. civil aircraft register.

Specifications (J/1U)

Data from Jane's all the World's Aircraft 1959-60

General characteristics

• Crew: 1
• Capacity: 1 passenger, with spray tank of 100 imp gal (120 US gal; 450 L) capacity
• Length: 23 ft 5 in (7.14 m)
• Wingspan: 36 ft (11 m)
• Height: 6 ft 2 in (1.88 m)
• Wing area: 185 sq ft (17.2 m²)
• Aspect ratio: 7
• Airfoil: NACA23012
• Gross weight: 2,350 lb (1,066 kg) typical with 50 imp gal (60 US gal; 230 L) of spray liquid
• Max takeoff weight: 2,650 lb (1,202 kg)
• Fuel capacity: Fuel: 32 imp gal (38 US gal; 150 L) ; Oil: 1.75 imp gal (2.10 US gal; 8.0 L)
• Powerplant: 1 × Lycoming O-360-A 4-cylinder air-cooled horizontally-opposed piston engine, 180 hp (130 kW)
• Propellers: 2-bladed McCauley variable-pitch propeller

Performance

• Maximum speed: 109 mph (175 km/h, 95 kn) at 2,350 lb (1,070 kg) at 1,000 ft (300 m)
• Cruise speed: 93 mph (150 km/h, 81 kn) at 2,350 lb (1,070 kg) at 1,000 ft (300 m)
• Stall speed: 34 mph (55 km/h, 30 kn) at 2,350 lb (1,070 kg) (flaps down)
  
• Recommended spraying speed: 60–80 mph (52–70 kn; 97–129 km/h)
• Rate of climb: 710 ft/min (3.6 m/s) at 2,350 lb (1,070 kg) with flaps
  
• Take-off run: 495 ft (151 m) in zero wind
• Take off-run to 50 ft (15 m): 1,980 ft (600 m) in zero wind

Further reading

• The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985). Orbis Publishing.
• Jackson, A.J. (1974). British Civil Aircraft since 1919 Volume 1. London: Putnam. ISBN 0-370-10006-9.

External links

• Auster Workmaster promotional brochure (PDF)