Photograph:
An artists impression of the Sadleir Air Bearing Fan installed in a four-seat executive – commuter aircraft
Country of origin:
Australia
Description:
Remote piloted vehicle
Power Plant:
One 800 kw (1,073 shp) turboshaft
Specifications:
- Wingspan: 9.00 m (29 ft 6¼ in)
- [Estimated – military variant] max speed: 445 km/.h (276 mph)
- Range: 370 km (230 miles)
- Loaded weight: 1,700 kg (3,748 lb)
- Payload: 350 kg (771 lb)
History:
In the 1980s VTOL Industries Australia Ltd of St George’s Terrace, Perth, WA devised, through its managing direct, Kim V Sadleir, a new approach to VTOL technology and much testing with two test rigs was carried out in an advance research and development stage. The first test rig was to test an innovative control system which demonstrated a 20-percent variation in lift and it was found the centre of pressure could be moved, plus or minus 10-percent of the fan-diameter, from the centre of gravity.
The second test rig was built to explore the design of various air-bearing shoes in a static mode, resulting in a preliminary design for a dynamic air bearing shoe. An all-composite fan supported by air-bearing shoes was built 2-meters (6 ft 6¼in) in diameter and this was powered by a converted motor vehicle engine. The test rigs were built to simulate the loads of a real aircraft and by late 1988 it was planned to replace this fan unit with a 5-meter (16 ft 4¾ in) delta-wing testbed with the aim of achieving controlled take-off, landing and hovering manoeuvres.
The company stated it believed the design had a number of parameters to which it could be applied, including remote piloted vehicle, model aircraft, light aircraft, subsonic and supersonic military applications, and eventually small commuter and business aircraft and later to a passenger carrying aircraft.
Work proceeded towards a series of inlet and outlet stator vanes with a fixed-pitch fan, each of these performing separate control and functional requirements. The tips of the blades were joined by a solid rim which was supported by multiple air-bearing shoes, thus eliminating wingtip deflection and allowing the fan to sit inside a conventional aerofoil section. Some of the advantages claimed were that it had a better potential than helicopters for high-speed flight and unrestricted manoeuvrability, better operating economics, and it could use conventional runway take-off and landing procedures. Various other designs were considered including the P-25T which would have been able to carry 80 passengers.
The four-seat executive commuter aircraft variant would have been powered by an aircraft piston engine. This model would have had a wingspan of 10.50 m (34 ft 5½ in), have a 5.00 m (16 ft 4¾in) fan and would cruise at between 241 to 278 km/h (150 to 173 mph) over a range of 741 km (460 miles). In the event the design did not proceed past the testing stage and eventually development stopped and the two test rigs were taken to the RAAFA Museum at Bull Creek in Perth where they were placed on display.