What happened
On 18 August 1999, a DHC-6 Twin Otter Series 310, registration VP-FBC, was performing a private flight for the purpose of recency and general handling at Oxford (Kidlington) Airport. During taxiing, the pilot followed a PA-31 along the taxiway, passing the control tower. Air traffic control had previously issued a warning regarding a PA-34 that was incorrectly parked, with its tail encroaching onto the taxiway.
As the pilot taxied along the taxiway centerline, his view of the left side of the taxiway was partially obstructed by a correctly parked Beech 200. While the pilot was monitoring aircraft parked on the right side of the taxiway to ensure clearance, a ground staff member signaled for the engines to be shut down. Following the engine shutdown, it was discovered that the top cover of the PA-34's tail fin had sustained minor damage after making contact with the left aileron/flap attachment bracket of the VP-FBC.
The investigation
Investigators examined the positioning of the aircraft on the taxiway and the visibility conditions for the pilot. The investigation established that the pilot's attention had been diverted from the left side of the aircraft to the right side while attempting to maintain clearance from parked aircraft. Furthermore, the physical configuration of the DHC-6 Twin Otter contributed to the incident, as the position of the engines made it difficult for the pilot to assess the clearance of the aircraft's wingtips.
Findings
- The pilot was unable to recognize the proximity of the incorrectly parked PA-34 because his attention was focused on avoiding other aircraft on the right side of the taxiway.
- Limited visibility of wingtip clearance due to the engine placement on the aircraft type contributed to the contact.