Piper PA 28-161 Cadet F-GIBQ Mountain Collision and Fire in Tourrettes-sur-Loup

Accident Overview and Immediate Circumstances On 11 November 2010 at approximately 12:05 local time, a Piper PA 28-161 Cadet, registration F-GIBQ, operated by a club, struck terrain in a valley north of the village of Tourrettes-sur-Loup (06), in the Caire sector. The aircraft caught fire and was destroyed. All occupants died. The pilot had departed from Cannes Mandelieu aerodrome (06) with two passengers at about 11:30. The planned route was to follow the coastal transit south of Nice and then return north of Nice via waypoint NA. At about 12:00, the aircraft passed waypoint NA at 1,800 ft and the pilot informed Nice information that he intended to continue toward Saint-Jeannet (06), Vence (06), and Tourrettes-sur-Loup. About three minutes later, the pilot told the controller he wished to turn north of Tourrettes-sur-Loup, “on the Caire,” before returning to his route. Two minutes after that, the aircraft struck terrain at 2,670 ft in a valley north of Tourrettes-sur-Loup and ignited. ## Terrain, Wreckage, and Witness Accounts The valley in which the accident occurred ascended from southeast to northwest, and the impact occurred near the bottom of the valley. Examination of the wreckage did not reveal a failure that could explain the accident. The propeller indicated that the engine was producing power at impact. Several witnesses, who were friends of the pilot and passengers, were in the valley near the Caire road. They saw the aircraft enter the valley toward them, climbing, then strike trees tens of meters from their position and catch fire. Other witnesses in Tourrettes-sur-Loup saw the aircraft pass overhead toward the valley at what they estimated to be a low altitude. ## Meteorological, Weight, and Performance Data Estimated weather conditions at the accident area were: temperature 15 °C, calm wind, and QNH 1011 hPa. The weight and balance calculation was prepared after the accident using estimated occupant masses and accounting for fueling before departure. Without considering possible baggage, the aircraft’s takeoff mass was 5 kg above the maximum takeoff mass. Based on fuel consumption indicated in the flight manual, the aircraft’s mass at the time of the accident was slightly below the maximum takeoff mass. Radar data showed that when the aircraft entered the valley, it was at 1,944 ft. At the last recorded point, 67 seconds after entering the valley and close to the accident site, the altitude was 2,644 ft. The average ground speed over that portion of the track was 78 kt. The average vertical speed over the same portion was higher than that given by the performance charts in the aircraft’s flight manual at maximum mass and under the same altitude, temperature, pressure, speed, and configuration. The aircraft’s performance, once it had entered the valley, was therefore insufficient to exit it.