What happened
On 21 August 2018, a Piper PA-3/1 Navajo, registered F-HGPS, was conducting a VFR aerial photography mission over the Peyrelevade and Ussel sectors in France. The flight, operated by IMAO, began at 10:09 local time with an estimated endurance of five hours. After completing the photography mission, the pilot began the descent toward Limoges-Bellegarde airport.
At 15:23, while descending below 3,000 ft, the pilot notified air traffic control that the aircraft was making an emergency landing due to fuel exhaustion. Shortly after this transmission, the aircraft struck trees and subsequently hit the ground approximately 2 NM south of the runway 03 threshold. The pilot and the operator sustained serious injuries, and the aircraft was destroyed.
The investigation
The BEA examined the wreckage and found no evidence of pre-accident technical failures. While the engine power was low upon impact, the fuel pump switches, tank selectors, and crossfeed were all in the correct operational positions. The investigation also focused on the aircraft's interior, noting that a heavy camera lift table, which was not secured, had shifted during the impact, contributing to the operator's injuries.
Investigators also reviewed the pilot's experience and the company's operational procedures. The pilot had significant experience but had not flown this specific aircraft type for approximately 22 months. Furthermore, the investigation identified discrepancies between the company's operations manual and the specific Supplemental Type Certificate (STC) instructions for the modified aircraft regarding the operator's required seating position during emergencies.
Findings
- The primary cause of the accident was fuel exhaustion.
- The pilot's estimation of remaining endurance was likely inaccurate, potentially due to a reliance on experience from a different aircraft type (PA-23) with greater endurance.
- The mission priority to maximize photo storage capacity before returning to base may have contributed to the depletion of fuel.
- A non-functional aircraft clock, which had stopped over an hour before the crash, may have provided a false sense of remaining flight time.
- The operator's serious injuries were exacerbated by the unsecured camera lift table and the fact that the operator was seated in the rear of the aircraft, contrary to the specific STC safety instructions for that modification.