What happened
On March 13, 2001, a Cessna T188C, registration EC-ECE, was performing agricultural spraying operations involving the distribution of solid fertilizer. During the tenth flight of the morning, while flying at a low altitude, the pilot initiated a right-hand turn. During this maneuver, the engine began to sputter and subsequently failed.
Due to the low altitude of the operation, the pilot was forced to perform an immediate emergency landing in a nearby fallow field. Prior to touchdown, the pilot followed standard emergency procedures by contacting the base of operations via radio and shutting off the magnetos, ignition systems, and fuel valves.
The landing site consisted of muddy terrain. As the aircraft touched down, the fertilizer spreader nozzle became snagged in the mud. This resistance acted as a pivot, causing the aircraft to capsize. The impact resulted in the aircraft landing in an inverted position, causing significant damage to the wings, propeller, engine, and tail section. The pilot sustained serious injuries but was rescued from the deformed cockpit by a person nearby.
The investigation
The investigation focused on the cause of the engine failure and the mechanics of the rollover. Investigators examined the propulsion system and found no mechanical damage or anomalies other than those caused by the impact. The propeller showed deformation on only one blade, which indicated that the engine was no longer producing power at the moment of impact, consistent with the pilot's report of an engine shutdown.
Regarding the fuel system, investigators noted that while one wing tank contained fuel, the other was empty. The investigation considered three hypotheses for the engine failure: a fuel system blockage, the presence of water in the fuel, or an interruption in fuel supply due to tank imbalance. While a blockage could not be entirely ruled out due to the lack of a post-accident fuel system examination, the empty tank provided a more direct explanation.
Findings
- The engine failure was likely caused by an interruption in the fuel supply to the engine.
- The imbalance in fuel levels—where one tank was empty while the other remained full—was likely due to the nature of agricultural spraying operations. Frequent turns in the same direction or the use of sideslips to compensate for crosswinds can cause fuel to shift to one wing.
- The pilot may have been unaware of the fuel imbalance because the aircraft's flight manual notes that fuel indicators are not reliable during non-standard maneuvers, such as sideslips or skids.
- The rollover and subsequent structural damage were caused by the fertilizer nozzle catching in the muddy ground during the emergency landing.