Background
On a regularly scheduled cargo service operated by Pel-Air Aviation Pty Ltd on behalf of Ansett Air Freight, an IAI 1124 Westwind aircraft registered VH-IWJ was conducting flight 474. The flight originated in Cairns, Queensland, and flew via Brisbane to Sydney, arriving at 2336 hours local time. After arrival, 1,350 liters of fuel were added to the tanks, and general cargo was loaded by Ansett Air Freight personnel. The flight plan indicated Instrument Flight Rules (IFR) procedures with an estimated 70-minute duration to Brisbane at Flight Level 370 (approximately 37,000 feet). The aircraft carried sufficient fuel for 164 minutes of flight; refueling was scheduled at Brisbane before continuing to Cairns.
Pel-Air intended to use the flight to assess the performance of a co-pilot under consideration for command upgrade. He occupied the left control seat, while the company Chief Pilot occupied the right seat.
Accident Sequence
At 0033 hours, the crew contacted Sydney ATC Clearance Delivery and received a "16 West Maitland One" Standard Instrument Departure (SID) for Runway 16. Shortly before 0049 hours, the crew contacted Sydney Control Tower, taxied, and executed a normal take-off. At 0056 hours, they established contact with Sydney Departures Control, advised they were climbing to Flight Level 370, and requested a direct track to Brisbane. The aircraft was equipped with a VLF/Omega navigation system capable of direct tracking. The Departures controller noted that the direct track would likely be available. That acknowledgment was the last recorded transmission from the aircraft.
Shortly before 0059 hours, the controller broadcast clearance for direct track at the planned altitude. No response was received, though radar returns remained visible momentarily before fading. The Distress Phase of search and rescue was initiated at 0100 hours.
Witnesses reported seeing aircraft lights descending rapidly toward the sea; the lights maintained their relative positions, indicating no rotation. The aircraft disappeared from radar approximately 11 kilometers southeast of Sydney Airport.
Search and Recovery
A search using helicopters and boats began. At 0245 hours, a helicopter sighted wreckage identified as from the aircraft. Police and Department of Aviation launches recovered pieces of structure, freight, and human remains. The degree of destruction indicated high-speed impact with the water. The main wreckage was presumed to lie in about 85 meters of water, 5 kilometers offshore from Botany Bay. Royal Australian Navy vessels and later a NSW Department of Fisheries vessel conducted an intensive underwater search, hampered by persistent unfavorable sea conditions. Operations were suspended in late November 1985. Subsequently, an internationally recognized underwater location and salvage expert was employed, and the wreckage was located and identified in 92 meters of water on 20 January 1986. Recovery of the Flight Data Recorder, Cockpit Voice Recorder, major portions of both engines, and other structural pieces was effected the following month.
Investigation Findings
The investigation reported the following findings: 1. There was a known malfunction of the rate of turn indicator. 2. The pilot in command possibly simulated simultaneous failures of all three flight attitude indicators. 3. There were no external references by which the crew could assess the attitude of the aircraft. 4. A loss of control of the aircraft occurred at a height of about 5,000 feet. 5. The crew did not recover control of the aircraft prior to impact with the sea.