What happened
On July 11, 2011, at approximately 21:00 local time, an Air Tractor AT-802A, registration EC-JLB, was engaged in firefighting operations near San Carles de la Rápita, Spain. The aircraft, operated by SAETA, was performing aerial work for the government of Catalonia. After completing an initial water drop, the aircraft headed to a local site to refill its tanks.
While attempting to take on water, the aircraft performed a water landing with its landing gear in the extended position. This caused the aircraft to capsize and remain floating upside down on the water's surface. The pilot was able to exit the submerged cockpit using an air bottle and escaped without injury. The aircraft sustained minor damage to the propeller blades and the left aileron.
The investigation
The CIAIAC investigation focused on why the landing gear remained extended despite the gear lever being positioned in the "up" position. Investigators found that the hydraulic pump circuit breakers (PUMP 1 and PUMP 2) were tripped. This prevented the hydraulic pumps from actuating the gear mechanism.
While the gear lever was correctly set to the up position, the lack of electrical power to the pumps meant the gear remained in its previous "down and locked" state. The investigation also examined the cockpit's visual and acoustic warning systems, finding both the green gear-down lights and the acoustic gear position warning system were fully operational. Furthermore, the investigation reviewed the pilot's use of checklists and the operator's procedures regarding the electrical breakers.
Findings
- The aircraft landed with the landing gear extended.
- The pilot had opened the hydraulic pump breakers prior to takeoff to reduce noise in the cockpit during flight preparation, a practice not documented in official procedures.
- Because the breakers were tripped, the gear retraction mechanism was inoperative, leaving the gear in the down position even though the lever was moved to the up position after takeoff.
- The pilot did not notice the gear position or the status of the breakers because checklists were not completed during the flight on at least four separate occasions.
- The operator's checklists were found to be poorly designed, featuring small font sizes and unnumbered items, which may have contributed to improper execution.
- The aircraft's visual and acoustic warning systems were functioning correctly and should have alerted the pilot to the gear configuration.