What happened
During a training session focused on stall and upset recovery, an instructor pilot initiated a wingover manoeuvre without briefing the student. While the aircraft's flight manual allows for wingovers provided the bank angle stays below 60° and the pitch remains under 45°, the instructor had not received specific training for this manoeuvre. During the execution, the instructor failed to maintain sufficient pitch before applying a rapid roll. This caused the aircraft to roll past the inverted position with a steep nose-down attitude.
In response to the descending attitude, the instructor reduced power to idle. While the instructor successfully managed the recovery to keep G-loads low—peaking at only 1.42 G—the lack of positive pitch input allowed the aircraft to accelerate rapidly. Consequently, the aircraft's speed increased by 20 knots beyond its never exceed speed, creating a risk of structural failure.
The investigation
The investigation focused on the sequence of the manoeuvre and the subsequent recovery process. It was determined that the instructor's lack of training in the wingover manoeuvre contributed to the loss of control parameters. Following the event, the instructor performed a visual inspection of the airframe and then returned control to the student to complete the planned stall recovery exercises.
Findings
- The instructor attempted a manoeuvre for which they lacked specific training.
- The aircraft's bank angle exceeded the 60° limit.
- The aircraft's speed exceeded the never exceed speed by 20 knots.
- The decision to continue the flight after the incident suggested that the potential for structural damage or control issues was not fully understood by the crew.