What happened
On 11 July 2018, a Pipstrel Alpha Trainer, registration F-JDGZ, was performing the final leg of a delivery flight from Slovenia to the United Kingdom. The aircraft was operating as a private flight with two occupants on board. Upon arriving at Clench Common Airfield in Wiltshire, the pilot in command decided to land on the 450 m grass runway after observing minimal wind conditions.
During the initial landing attempt on Runway 26, the aircraft bounced, prompting the pilot to execute a go-around. Control of the aircraft was transferred to the pilot in the right seat for a second approach. The aircraft touched down roughly one third of the way down the runway, but the pilot determined that braking would be insufficient to stop the aircraft and initiated another go-around.
As the aircraft became airborne, the pilot flying began a slight right turn to clear trees on the departure path. During this maneuver, the pilot noticed degraded climb performance and realized the airbrakes were still extended. The pilot in the right seat instructed the pilot in command to retract the airbrakes. However, the pilot in command retracted the flaps instead of the airbrakes. This error caused a sudden loss of lift, resulting in the aircraft sinking into a corn field at the end of the runway, where it struck a wire fence.
The investigation
The investigation focused on the sequence of events during the second go-around and the specific actions taken by the crew. Investigators examined the aircraft's configuration, noting that the airbrakes were extended during the climb. The investigation established that the pilot in command had access to the electrically-driven airbrake controls, which were positioned directly in front of him. The investigation also reviewed the flight's context, noting the aircraft was on a delivery mission and that the pilot in the right seat was a qualified instructor.
Findings
- The aircraft sustained damage including a bent nose gear strut, a cracked engine cowling, and scratches to the propeller and wing.
- There were no injuries to the two occupants.
- The primary cause of the loss of altitude was the unintended retraction of the flaps by the pilot in command, which occurred in response to a command intended for the airbrake controls.