What happened
On September 9, 2000, at approximately 20:15, a PZL M-18A, registration EC-FAY, departed from its base in Rosinos de la Rejada, Zamora, to respond to a forest fire at Laguna Truchas. The aircraft was operating in a commercial aerial firefighting capacity, carrying a load of water mixed with foam.
Shortly after takeoff, while established in steady flight, the aircraft experienced a partial loss of engine power. The pilot attempted to return to the base, jettisoning the water load and activating both electric and manual emergency fuel pumps. Despite these efforts, the engine power did not recover, and the aircraft continued to lose altitude. During the descent, the pilot observed that the fuel pressure indicator had dropped to zero. Unable to reach a suitable emergency landing site, the pilot deployed flaps, opened the emergency door, and shut off the master switch and fuel supply in an attempt to mitigate the impact. The aircraft struck the ground and was destroyed by a post-impact fire.
The investigation
The investigation focused on the engine's performance and the fuel delivery system. Two days prior to the accident, a 100-hour inspection had been performed, which included replacing the engine's fuel pump due to previous indications of low fuel pressure.
Due to the extensive damage caused by the post-impact fire, investigators were unable to perform a detailed examination of the engine, fuel pumps, or control lines. However, the investigation examined the pilot's actions and the aircraft's maintenance history. The investigation also considered a manufacturer's service letter issued after the accident, which noted that a throttle control cable could potentially jam, though investigators noted such a failure would not explain the drop in fuel pressure.
Findings
- The aircraft experienced a partial obstruction in the fuel system following the fuel pump.
- The drop in fuel pressure to zero suggests an obstruction in a component such as a filter or flexible piping, located between the pump and the pressure gauge.
- This obstruction may not have been apparent during the previous ferry flight from Valencia because the power requirements during that flight were significantly lower.
- A total closure of the fuel shut-off valve was ruled out, as such an event would have caused the engine to stop completely rather than just lose power.
1 pilot survived the crash with injuries, including a fractured nose, jaw, and foot.