Piper PA-25-260 Crash During Agricultural Training at Palma del Río (EC-CXL)

Incident Overview and Location On Friday, April 11, 2003, at 14:15 local time, a single-engine Piper PA-25-260 Pawnee, registration EC-CXL, crashed at the Sebastián Almagro aerodrome in Palma del Río, Córdoba. The aircraft was destroyed, and the pilot sustained minor injuries. Minor damage was also reported to an olive grove near the crash site. The aircraft was powered by a single Lycoming O-540-G2A5 engine and was used for agricultural operations, with a maximum takeoff weight of 1,315 kg and a maximum load capacity of 544 kg. The specific aircraft was built in 1976 and equipped with a two-blade fixed-pitch propeller. The power and mixture controls were located close together, with the throttle featuring a ball and the mixture control a star-shaped end. The training procedure for water discharge involved the pilot moving their left hand to the water discharge lever during the takeoff roll to quickly discharge water in case of an engine failure. After rotation, the hand would return to the throttle. According to the aircraft's maintenance manual, the seatbelt and harness system was inspected every 100 flight hours. The pilot was a 29-year-old commercial pilot with 430 total flight hours, including 17 hours on the PA-25 type. He was undergoing training to obtain an agricultural pilot qualification, following the program established by Resolution RL 2001/10. He had already been soloed in the aircraft and needed approximately one more hour of flight time before the final tests. The instructor, who was observing from the ground, held multiple qualifications including agricultural, single-engine turbine, single-engine piston, VFR day and night, flight instructor, and agricultural flight instructor. She had 1,480 total flight hours, 790 as an instructor, and 120 hours on the AT-802 turbine engine. The pilot was not wearing a helmet, only headphones. He had started a first training period of circuits and water discharge at 9:30, which lasted about 1 hour and 20 minutes. After a rest, he began a second training period, during which he performed a water discharge and landing, then took off again after the aircraft was loaded with an estimated 300 to 400 liters of water. The aircraft took off from runway 25 and, at about 100 feet altitude on the runway heading, the pilot reduced engine power slightly to level the aircraft and then turn left to position for a water discharge in the tailwind, as was customary during training. Normally, the engine RPM was reduced from 2,500 to about 2,400. After reducing power, the pilot noticed the aircraft was not flying well and the engine was behaving abnormally, so he advanced the throttle to full. The situation did not improve, so he decided to discharge the water while still on the runway heading. At the moment of discharge, the aircraft became unstable and reached a very high pitch-up angle that could not be controlled until it entered a stall and fell from the left wing. The pilot remembered seeing the stall warning light. The aircraft then crashed, impacting several olive trees and the ground in a nose-low, left-banked attitude, coming to rest without skidding much. The final fuselage heading was about 45°, a change of about 205° to the left from the original 250° heading. During the impact, the shoulder harness detached from its upper rear attachment, and the pilot's head struck the instrument panel. Although he suffered a severe blow and was bleeding, he was able to exit the aircraft on his own. Witnesses ran to the aircraft and helped the pilot, who was taken to the Palma del Río health center and then to the Córdoba Hospital, where he was discharged hours later. The aircraft suffered extensive damage to the propeller, engine mount, fuselage, and wing, and was considered destroyed. The fuel tank ruptured, spilling all its contents, but there was no fire. The left semi-wing, heavily damaged and twisted from the tip with the leading edge backward, and the tail skid, came to rest on two damaged olive trees. The wreckage was located about 30 meters from the end of runway 25 and about 40 meters to the left of its centerline extension, with the fuselage heading at about 45°. The aircraft's nose was about 17 meters from a nearby road. A telephone line about 4 meters high in the area was not struck by the aircraft. The propeller cone and left engine cowling were crushed. The upper engine mount attachments detached from the fuselage, causing the engine, with the propeller still attached to its hub, to tilt forward and rotate to the right as seen from the cockpit. The propeller showed marks on the leading edges of the blades and deformation from flexing and slight twisting at the tips of both blades, indicating it was rotating at low power when the impact occurred. The rear fuselage cone and tail surfaces showed minor damage. The flight cabin was not crushed, but the instrument panel showed a mark from being struck by the pilot. The harness detached from its upper rear attachment, which comes from the take-up reel. The pilot unbuckled his seatbelt and harness and was able to exit the aircraft. One of the first people to arrive at the scene to help the pilot stated that the throttle lever was forward, the mixture lever was halfway, and the discharge lever was forward. These individuals moved the controls back and cut all switches as a safety measure. A witness with aeronautical knowledge near the runway saw the takeoff but not the water discharge. When he saw the aircraft again, he observed the nose was very high, and then the aircraft 'turned left'. He thought the aircraft had lost speed and then saw it enter a stall. In his opinion, the engine was running when the aircraft stalled. The pilot remembered that the seatbelt and harness held him to some extent during the accident, but he eventually struck his head on the instrument panel, resulting in minor injuries in the form of cuts and bruises. The harness and its take-up reel, P/N O-4600-444-1, s/n 837, manufactured by American Seating Co., Specification AN-R-29(2), were inspected to determine their behavior during the impact. The two shoulder harness straps join at the top and are attached to a 115 cm braided steel cable, which in turn is attached to a screw with a hollow opposite end. In this hollow, the end of another cable is engaged and compressed with a nut, which enters and exits the take-up reel, winding around a spring as needed to adjust the harness. The pilot can block the reel's rotation by operating a two-position lever. In one position, the cable enters and exits the reel freely until it reaches a stop, at about 42 cm of extension. In the other position, the reel is locked at the current cable extension. During the inspection, no inertia mechanism was observed in the reel. It simply has a torsion spring that collects the excess cable and therefore pulls the harness backward when the system is not locked with the lever. The pre-flight operation mode involves the pilot adjusting the harness according to their build and comfort preference, then placing the lever in the locked position, so the cable neither enters nor exits the reel and the pilot is held by the shoulder harness at all times. However, the type certificate holder reported that, although they could not contact the part manufacturer (American Seating Corporation) for technical details, the system was indeed inertial, did not require maintenance, and was not recommended to be disassembled, as it would lose its calibration as an inertial belt. The reel should absorb a load of 615 lb (pilot weight: 170 lb, with 9 g applied and the shoulder harness absorbing 40% of the load). This data comes from CAR 3.386 a) and the Technical Standard Order (TSO) C-22. It was verified that