The handling pilot was undergoing a scheduled 6-monthly proficiency check in the Learjet, under the supervision of an experienced instructor who occupied the right control seat. The flight was planned to depart from Essendon and proceed to the Ripley locator, for an entry into the holding pattern, before making a locator approach to Avalon. Three touch-and-go circuits were planned at Avalon, including one 700-ft asymmetric low-level circuit following a simulated engine failure at V1. The aircraft was then to return to Essendon via the Plenty locator for an instrument landing system (ILS) approach.
The instructor briefed the exercise in detail and, because the pilot under check had low experience in the Learjet, it was decided that the instructor would handle all radio communications and conduct the necessary check sequences. The instructor also indicated that it was company policy for the aircraft be landed with less than full flap during an asymmetric landing. The aircraft was to be landed with flap 20 at Vref +10 kts.
The flight proceeded normally up to the point of the simulated engine failure at V1. When the instructor simulated a right engine failure by placing the thrust lever in the IDLE position, the aircraft drifted to the right. Intervention by the instructor enabled the aircraft to return to balanced flight. The handling pilot continued to carry out the 700-ft circuit in the after-take-off configuration of gear UP and flap 8. Flap 20 was selected during the base turn. The aircraft was flared normally with both thrust levers in the IDLE position. As the aircraft settled, a slight vibration was noticed, and both pilots became aware that the landing gear was still selected UP. Go-round power was applied and the aircraft climbed away. The landing gear was cycled normally and the aircraft returned for a full stop landing. A subsequent inspection of the aircraft showed that the only evidence of a runway strike was abrasion of the lower fuselage mounted very high frequency (VHF) blade antenna.
A subsequent investigation revealed that the pilot under check was allocated one hour of Learjet flying every 3 months. The instructor had selected the flight sequences to give the pilot the maximum handling exposure in the limited time available. In doing so, the normal two-crew, challenge and response routines were abandoned and the checks had to be accomplished by the instructor alone. The instructor became distracted by the asymmetric handling issues, and the demands of the low-level circuit, subsequently forgetting the relevant downwind and pre-landing checks. The handling pilot, who had been absorbed with controlling the aircraft, had lost situational awareness and did not notice the lack of check procedures by the instructor, or the lack of a positive gear-down indication.
The approach had been carried out with flap 20 extended, rather than full flap (flap 40), because the operator had previously experienced a partial loss of control during training when attempting an asymmetric go-around at flap 40. However, with flap 20 selected, the landing gear warning system was inhibited, contributing to the late realisation that the landing gear was not extended. The flap 20 asymmetric approach configuration was not in accordance with the manufacturer's flight manual recommendations.