What happened
On 3 May 1998, a Jabiru SK, registration G-BXAO, was performing a private flight departing from Shobdon. Shortly after takeoff, the right-hand side of the upper engine cowl became unseated and lifted away from its position, though it remained partially attached by a single pin and clip on the left side. As the cowl moved upward, it struck the propeller, resulting in minor damage to the propeller tip.
The movement of the cowl created substantial aerodynamic drag and obstructed the pilot's visibility. Consequently, the aircraft was unable to gain altitude and remained at approximately 100 feet, following the runway centerline. The pilot communicated an intention to perform a left-hand circuit; however, during the initiation of the turn, the left wing dropped and the aircraft entered a stall. The aircraft subsequently crashed into an orchard filled with young apple trees.
A pilot flying a following Robinson R22 observed the impact, landed in a nearby field, and reached the wreckage to shut off the battery master switch and the fuel cock. Despite the aircraft being beyond economic repair, both occupants sustained minor injuries and were able to exit the wreckage unassisted.
The investigation
The investigation focused on the mechanism of the engine cowl's failure. The top engine cowl is a single-piece component secured by over-centre latches on both sides, with 'R' clips used as safety devices. Although the latch and clip were found in the closed position following the accident, investigators determined there was a high probability that the latch had not been properly engaged with the bottom cowl attachment point. It was noted that if the latch is not fully engaged, the cowl can appear flush and secure during a brief pre-flight inspection despite being unstable.
Findings
- The engine cowl became loose during the takeoff phase, causing increased drag and obscured vision.
- The failure was likely caused by the latch not being properly engaged with the lower cowl attachment.
- The aircraft entered a stall during a turn due to the aerodynamic consequences of the cowl failure.