Beech A36, Pickertaramoor NT, 10 October 1988

On arrival at his destination, the pilot joined the circuit on the downwind leg and used the pitch lever to signal his arrival to the ground party. He then distracted himself by cancelling his SAR watch by radio. By this time he had flown past the windsock and it was no longer in view. This distraction continued while he tried to recall the wind direction and decide if he should go around and check the windsock. Deciding to continue the approach, he positioned the aircraft on final but only carried out his final approach checks in a perfunctory manner and did not positively check the gear down indications. The aircraft subsequently landed wheels up and neither the pilot nor the passengers recalled hearing the undercarriage warning horn sound.

Detailed investigation showed that the warning horn micro-switch actuator on the throttle assembly was defective and of a faulty design. The subject component had been redesigned by the manufacturer, however, the modified component still bore the same identification number as the superseded item. In addition, the component of faulty design was still available in the spares inventory.