What happened
During a visual approach, the flight crew of VH-EWW, a Cessna 172, encountered difficulties following an instruction from the aerodrome controller to maintain "best speed" until crossing the runway. Unsure of how to comply with the non-standard phraseology, the crew did not seek clarification. To manage the flight path, which was steeper than a standard 3° profile, the crew reduced throttle to idle and lowered the nose. This resulted in an approach speed of 90 kt, significantly exceeding the limits specified in the P/OH and the operator's stabilized approach criteria.
As the aircraft crossed the threshold, the high airspeed caused the aircraft to float far down the runway. Upon landing, the application of brakes caused the wheels to lock. While attempting to turn onto taxiway GOLF, the aircraft skidded off the taxiway into the grass. In an attempt to avoid a drainage ditch, the instructor applied full throttle and back pressure, which caused the fuselage and tail to strike the ground. The crew then initiated a go-around from the grass, during which the aircraft's airspeed dropped to the point of triggering a stall warning, leading to a low climb gradient and a near-collision with hangars.
The investigation
The investigation examined the communication between the controller and the flight crew, as well as the aircraft's performance during the landing phase. It was noted that the controller's use of the term "best speed" was not part of standard Airservices Australia phraseology. The investigation also reviewed the crew's failure to execute a go-around despite the approach being unstabilized and the aircraft exceeding the maximum allowable approach speed.
Findings
- The controller's instruction to maintain "best speed" contributed to the excessive airspeed during the approach.
- The flight crew failed to seek clarification regarding the non-standard instruction.
- The crew did not initiate a go-around despite the approach failing to meet stabilized approach criteria.
- The high landing speed reduced braking effectiveness, leading to the loss of control on the taxiway.
- The instructor's decision to avoid a ditch resulted in the aircraft's tail striking the ground.