What happened
On 16 July 2005, a Staaken Z-21 Flitzer, registration G-ERIW, was performing a private flight at Popham Airfield in Hampshire. During the landing phase, the pilot initiated a standard approach to the grass runway 03. As the aircraft entered the flare, the hand grip attached to the control column unexpectedly slid along the steel shaft. This sudden loss of control caused the nose of the aircraft to pitch downward, resulting in the aircraft striking the ground before pitching onto its back. The pilot, who was secured by a four-point harness, exited the open cockpit without any injuries.
The investigation
The investigation focused on the mechanical failure of the control column assembly. It was determined that the hand grip, which had been constructed from turned wood and attached to the steel shaft using a friction fit, failed during the landing maneuver. Evidence indicated that recent high temperatures had caused the wooden component to crack. This structural degradation of the wood allowed the grip to move freely along the shaft, rendering the pilot unable to maintain pitch control during the critical flare stage.
Findings
- The primary cause of the accident was the failure of the wooden hand grip to remain fixed to the control column shaft.
- Recent hot weather conditions had caused the wooden grip to crack.
- The use of a friction fit was insufficient to prevent the grip from sliding once the wood had been compromised by heat-induced cracking.