Accident Overview
On 5 July 2005 at approximately 16:30 local time, an Air Tractor AT-802, registration EC-GUF, was destroyed during a firefighting mission near Castellbisbal, in the province of Barcelona, Spain. The aircraft, operated by Avialsa, had been contracted for the fire prevention and firefighting season and was based at Sabadell airport, about 30 km northeast of Castellbisbal. The sole occupant, the pilot, suffered minor injuries and evacuated the aircraft after it caught fire.
Flight Details
The flight departed Sabadell at 16:15 for its second sortie of the day. The first flight, also by the same pilot, had taken off at 13:30 and lasted 1.5 hours. The accident occurred when the aircraft, after performing a water drop at the leading edge of a wildfire, failed to regain altitude. The drop was executed at very low altitude, after which the aircraft entered a column of smoke and lost altitude while flying over several streets in the Castellbisbal urban area. It collided with a public street lamp, then impacted the terrain beyond the road, slid down a hillside through orchards, and came to rest at the bottom of a streambed in Can Cases de la Iglesia, where it caught fire. The aircraft was completely destroyed. Minor damage was reported to a street lamp and vegetation.
Aircraft Information
The aircraft was an Air Tractor AT-802 (serial number 802-0059, year of manufacture 1997) with registration EC-GUF. It was powered by a Pratt & Whitney Canada PT6A-67AG engine (1,350 SHP) driving a five-blade Hartzell HC-B5MA-3D propeller. The maximum takeoff weight was 7,260 kg, and the water capacity was 3,032 liters (3,992 kg). At the time of the accident, the aircraft had accumulated 1,971:25 flight hours. The last periodic inspection (100-hour) was performed on 12 May 2005 at 1,912:50 hours.
Pilot Information
The pilot, aged 54, held a Commercial Aircraft Pilot License with VFR-HJ, single-engine, and firefighting ratings. He had a total of 12,000 flight hours, approximately 57:45 hours on the type. In the 30 days prior to the accident, he logged 17:35 hours, including 1:45 hours on the day of the accident during the previous flight.
Accident Sequence
According to the pilot's statement, he executed the water drop without incident after reconnoitering the drop site. Following the drop, he inadvertently flew into an area of dense smoke for about two seconds. After exiting the smoke, he attempted to increase power but found the engine unresponsive. He reported the engine failure by radio (the message was reportedly unintelligible to firefighting personnel) and attempted to restart the engine without success. Subsequently, the aircraft struck a street lamp and then the ground. The aircraft began to burn, and the pilot evacuated under his own power.
Investigation Findings
A visual inspection of the wreckage indicated that the engine controls, tubing, and accessories, particularly those for the fuel, were destroyed or severely damaged by the post-crash fire. The cockpit controls, especially on the left side, were also heavily damaged. The propeller was found feathered. A detailed disassembly and analysis of the engine at the manufacturer's facilities in Canada revealed no signs of malfunction that would have prevented normal operation prior to the accident. At the time of impact, the engine showed signs of rotating under low or no power. Heat and fire damage precluded an operational analysis of the controls and accessories, particularly those of the fuel system. No meteorological data were available from the fire location, but nearby stations indicated good visibility, light winds from the southeast at 6 to 7 knots, low scattered clouds, and no precipitation.