What happened
On 17 May 2004, a Piper PA-28-161 Cherokee Warrior II, registration G-BNOH, arrived at Old Sarum Airfield in Wiltshire following a flight from Sherburn-in-Elmet. After landing on Runway 24, the pilot, who was unfamiliar with the airfield, sought guidance regarding the next steps for backtracking. Air/ground radio personnel instructed the pilot to "EXIT RIGHT AND TAXI OUTSIDE THE YELLOW CONES," directing the aircraft toward a section of recently mown grass.
Believing this area to be a taxiway, the pilot and passenger proceeded toward the parking area. As the aircraft moved through the grass, the left wingtip area struck a tall metal fence post that was partially obscured by a bush. The impact resulted in a dent to the wing's leading edge, approximately three feet from the wingtip. Following the collision, the aircraft was moved to a parking position, where a maintenance engineer inspected the damage and grounded the aircraft.
The investigation
The investigation examined the airfield layout and the clarity of the instructions provided. Old Sarum utilizes a large, single field where various maneuvering and parking areas are delineated by white and yellow cones. The investigation found that the smooth, well-maintained appearance of the grass made it difficult to distinguish between different sections of the airfield from the cockpit.
Furthermore, the investigation noted that while the pilot possessed relevant aeronautical charts, these documents lacked the specific detail required to differentiate the taxiing area from the parking area. The radio operator's instruction was also found to be potentially ambiguous, as the phrase "outside the yellow cones" could be interpreted from different perspectives relative to the cones' position.
Findings
- The pilot was unfamiliar with the specific layout of Old Sarum Airfield.
- The instruction provided by the radio operator was ambiguous regarding the intended direction of travel.
- A metal fence post, which caused the damage, was poorly visible because it was hidden behind vegetation.
- The uniform appearance of the mown grass across the airfield contributed to confusion between maneuvering and parking zones.