Introduction
On 10 January 1998, a Grumman G 164A aircraft, registration CS-APW, operated by AGROAR – Trabalhos Aéreos Lda., was involved in an accident near S. Miguel de Machede, Portugal. The aircraft was conducting an aerial chemical weeding flight.
Sequence of Events
The aircraft departed from the agricultural strip of Álamo, near S. Miguel de Machede, to perform aerial chemical weeding. Approximately two minutes after takeoff, a partial loss of engine power occurred, accompanied by significant fluctuations in engine rpm. Unable to maintain altitude, the pilot decided to jettison the entire chemical load and execute an emergency landing in a terrain with a slight upward slope. The approach was made with a headwind at an indicated speed of 75 knots. During the final approach, the pilot felt the aircraft sinking excessively, attributing it to a downdraft. Despite immediate corrective action, the aircraft struck the ground violently, first with the tailwheel, then the main landing gear, and finally came to rest inverted.
Injuries and Damage
The pilot, the sole occupant, sustained no injuries and was able to exit the aircraft unassisted. The aircraft was partially destroyed. There were no injuries to others or damage to third-party property.
Probable Cause
The investigation was unable to determine the cause of the engine failure. The evidence available did not allow identification of why the engine lost partial power. Consequently, the probable cause is listed as undetermined.