Goulburn

The aircraft was being used to transport equipment for members of an Aero Club, who were to carry out training at Goulburn. As the pilot was undergoing formation flying training, it was decided that he would lead a formation of two aircraft for the flight. A briefing on the procedures to be followed was carried out. During the flight the pilot of the second aircraft began to suspect the accuracy of his aircraft's airspeed indicator and requested that it be checked against that of the lead aircraft as the aircraft joined the circuit. The pilot of the lead aircraft extended the landing gear and flew the initial leg of the circuit at an indicated airspeed of 96 knots. At the end of this leg the pilot turned the aircraft steeply to the left, the nose dropped slightly and the aircraft flicked into a steep right turn. The aircraft then assumed a steep nose down attitude, however, the pilot was able to level the wings and raise the nose to the level attitude before impact. The impact occurred at a very high rate of sink. The pilot had not previously practiced steep turns at relatively slow airspeed and was not aware of the stalling speed in the given configuration and attitude. The pilot was subsequently unable to recall the reason for attempting a steeper than normal turn. When the aircraft stalled the pilot was unable to effect a full recovery in the height available before impact with the ground.

Prior to departure the pilot had received a weather forecast which indicated that fog could be expected at the destination. Adequate fuel was carried in the aircraft tanks to allow for a considerable period of holding and/or a diversion to another aerodrome if required. After an apparently normal flight of 35 minutes the aircraft arrived in the Goulburn area and the pilot reported his intention to carry out a standard instrument approach. The manoeuvres associated with this procedure do not involve flight over the city of Goulburn, however witnesses observed the aircraft as it circled over the city several times at a relatively low height. It was then seen to roll and descend steeply before striking two houses. A fierce fire broke out which engulfed the aircraft and both residences. The three persons on board the aircraft and a person in one of the houses received fatal injuries. A detailed inspection of the wreckage revealed that the camshaft of the left engine had failed in flight and the pilot had apparently feathered the propeller. The engine was not operating at the time of impact. No other defect or malfunction was discovered which might have contributed to the development of the accident. It was determined that the particular camshaft had failed from fatigue cracking, resulting from defective manufacture. It was considered likely that when the aircraft arrived over Goulburn, shallow fog obscured all or part of the aerodrome. The lights of the city would have been clearly visible and the pilot probably decided to use the city, rather than the nearby radio navigation aid, as a convenient holding point while waiting for conditions at the aerodrome to improve. During a series of left hand orbits, and after advising his intention to conduct an instrument approach, the pilot experienced a complete failure of the left engine. In order to realise the available single-engine performance of the aircraft the pilot had to perform a series of checks and actions which would result in the applicable propeller being feathered; any unnecessary aerodynamic drag being reduced; and an appropriate airspeed being established. It was determined that although the propeller had probably been feathered, the landing gear, which had evidently been lowered previously, had not been raised to reduce drag. In addition, an analysis of radar returns from the aircraft, recorded at Canberra, indicated that the airspeed at which the aircraft was flying shortly before radar contact was lost, was less than the optimum figure. The final manoeuvre described by witnesses was consistent with that which follows a loss of control in twin engine aircraft when power is being supplied by only one engine and the speed is below the minimum required for full control. The reason the pilot did not raise the landing gear and maintain the required minimum control speed could not be established.

The pilot contacted Sydney Flight Service Center at 1849, advised he was taxiing for runway 22 and that he would call again on departure. No further transmissions were received from the aircraft. VH-TDU completed an apparently normal take off and the landing gear was retracted. Shortly after it became airborne, it entered a gradual descending left turn and flew into the ground. The initial impact was on the left wing tip, approximately 1700 metres south of the departure end of Runway 22, at a speed of about 125 knots. The aircraft bounced, rolled inverted and again struck the ground some 100 metres further to the east. It then ;slid across the ground for a further 230 metres. A small fuel-fed fire broke out in the right wing but died out after several minutes. Five occupants were slightly injured while the captain was killed. Examination of the wreckage found no evidence of pre-existing mechanical malfunction or defect, apart from an open circuit in the gyro motor of the pilot's turn co-ordinator instrument. The instrument was not subjected to mechanical damage during impact and it is likely the fault existed prior to the accident. It could not be determined whether the pilot was aware that the instrument was unserviceable. All other instruments, including the primary flight instruments used in aircraft attitude control, were found to be serviceable and calibrated within specified limits. There was no evidence of pilot incapacitation prior to impact. Injuries were such that he was unable to recall details of the final flight. The passengers were not aware of any abnormality until the aircraft struck the ground. The pilot's current log book was not located. Therefore, while it is known that he had considerable experience at flying Cessna 340 aircraft, his hours on this type are unknown.

The aircraft arrived at Goulburn at 0800LT and was supposed to continue to Sydney. Weather conditions deteriorated and both occupants, Cpt E. W. Cornish, owner of the aircraft and his pupil, G. K. Wride, were advised by Cpt Matheson, an instructor with the Goulburn Aero Club, not to continue the flight. Nevertheless Cornish elected to carry on and evidently Wride was in control when the aircraft, flying at around 100-150 feet, nose dived onto a stony ridge located 3 miles from Marulan. The aircraft was destroyed and both occupants were killed.

Source: Ed Coates.