Background
On 21 July 2000, at 07:00 local time, a single-engine Piper PA-36-300 (registration EC-HOF) was engaged in commercial agricultural spraying operations over rice fields in the Delta del Ebro, Tarragona province. The aircraft, manufactured in 1981, was equipped with a Lycoming IO-540-K1G5 engine. The pilot, a 34-year-old commercial pilot with 2,700 total flight hours, held a valid license.
Flight Sequence
While spraying, the pilot observed that full throttle and maximum RPM were required to maintain altitude. He noted vibrations and exhaust explosions, suspecting a cylinder malfunction. He jettisoned the load and headed back to the airstrip. The pilot activated the electric fuel boost pump without improvement. After about two minutes, the engine seemed to recover, but fuel flow indicated consumption was very high. Turning off the electric pump produced no change. Attempting to lean the mixture caused the engine to vibrate and exhaust explosions to resume; richness restored normal operation.
Approaching the airstrip, the pilot reduced power to lower flaps for landing, and the engine again ran rough. Although it accelerated briefly, it never fully recovered. While on a right base leg for landing, the pilot saw another aircraft taking off from the same airstrip. He added power and began a 360-degree turn to sequence behind the departing aircraft. After about 150 degrees of turn (roughly 80 degrees relative to the runway), the engine lost power rapidly, and the aircraft descended toward a rice field. The pilot turned sharply left toward the runway but could not reach it, impacting the field about two meters from the strip. The aircraft bounced and came to rest on the runway.
Injuries and Damage
The pilot was uninjured. The aircraft sustained substantial damage to the propeller, engine, landing gear, and lower structure. No other damage occurred.
Investigation
The engine was inspected per airworthiness directive AD 91-14-22 and service bulletin SB 533A. Cracks were found in the crankcase, but these were attributed to impact. The alternator was in poor condition; the electric fuel pump was replaced because fire extinguisher residue had contaminated it. The engine was tested on a bench and reinstalled, and it was found serviceable. No pre-impact mechanical anomalies were identified.
Witnesses reported that the landing aircraft and a departing aircraft were using opposite runway directions simultaneously. The airborne aircraft executed an evasive maneuver and then crashed into the adjacent field.
The pilot stated that the area where problems began had suitable emergency landing sites, but to return to the airstrip he had to cross the Ebro River, which was 300–400 meters wide at that point.
Analysis
The investigation noted that using opposite directions for takeoff and landing is common in agricultural operations due to field configuration, product application requirements, and efficiency. The pilot's decision to continue to the airstrip despite engine concerns involved crossing a wide river, which was deemed risk acceptance. Reducing power during the approach, which worsened the engine's behavior, was considered suboptimal given the circumstances.
Conclusions
The most probable cause of the incident was that the landing aircraft could not successfully complete the evasive maneuver required by the presence of another aircraft on the runway. This maneuver was performed at reduced speed, altitude, and power—normal for landing—but became critical due to possible engine problems that had been present for several minutes and may have worsened in the final moments. The use of the runway in both directions was not considered a contributing factor.