What happened
On September 15, 2019, a Piper PA31-350 (registration HK-5229), operated by Transpacíficos S.A.S., was performing a scheduled VFR flight from Popayán’s Guillermo León Valencia Airport to López de Micay. The aircraft was carrying two crew members, seven passengers, and approximately 170 lbs of baggage.
After beginning its takeoff roll on runway 26, the aircraft rotated at 14:06:06 local time. Witnesses observed a very low climb gradient immediately following rotation. Approximately 20 seconds into the flight, the aircraft lost altitude and entered a steep, 60-degree right-hand descending turn. The aircraft struck trees and eventually collided with the roof of a house in the Junín neighborhood of Popayán. The impact destroyed the aircraft and caused significant structural damage to two nearby homes. Of the nine people on board, seven fatalities were recorded, while two passengers sustained serious injuries.
The investigation
The GRIAA investigation focused on the aircraft's performance during the takeoff phase. Investigators found that the takeoff roll spanned 3,146 feet, which was 45% longer than the required distance for maximum takeoff weight. While the aircraft managed to lift off due to ground effect, it was unable to maintain a safe climb once it climbed out of that effect.
Technical analysis revealed that the aircraft was operating under high-density altitude conditions (7,934 ft). The investigation also determined that the aircraft's center of gravity was outside of limits, positioned behind the aft limit. Furthermore, the aircraft was likely operating at an overweight condition of approximately 469 lbs above its intended weight, which significantly reduced its maneuverability and stall margin.