Plain, Valley

The pilot, sole on board, departed Geneva-Cointrin Airport on a private flight to Genk-Zwartberg Airport where the aircraft was supposed to follow a maintenance program. The single engine aircraft departed runway 23 at 1157LT and continued to climb in IMC conditions. About 30 seconds after he was transferred to the departure frequency, the pilot was cleared to climb to FL090. At an altitude of 4,200 feet and at a speed of 142 knots, the aircraft climbed steeply then veered to the left. About 12 seconds later, the aircraft stopped to climb and another period of 8 seconds was necessary to stabilize and to follow the route. At 1159LT, the aircraft deviated to the left during 20 seconds, drifting about 555 metres from the runway axis. After following various headings with huge variations in ground speed and altitude, the aircraft entered an uncontrolled descent and crashed in an open field located in Sézenove, about 7,8 km southwest from Geneva-Cointrin Airport runway 05 threshold. The aircraft disintegrated on impact and the pilot was killed.

The aircraft was completing a geophysical mission on behalf of Xcalibur Airborne Geophysics, with two pilots on board. En route, the crew encountered an unexpected situation and attempted an emergency landing. The aircraft crash landed in a rocky terrain, lost its undercarriage and came to rest. Both occupants escaped uninjured and the aircraft was damaged beyond repair.

The crew (a pilot and a load master) was performing a regular cargo service to Karisparu and departed Mahdia Airport at 1142LT. The duration of the flight should be less than 20 minutes as the aircraft was scheduled to arrive at Karisparu Airfield at 1200LT. Less than three minutes after departure, the radio contact was lost with the pilot. SAR operations were initiated but after four days, no trace of the aircraft nor the crew was found. The Director General of the Guyana Civil Aviation Authority (GCAA), Zulfikar Mohamed, said that the crucial 72-hour window period since the aircraft vanished in the thick jungle in Region Eight expired on Tuesday December 30. On January 4, 2015, all SAR operations were suspended as no trace of the aircraft was found.

The crew was performing a flight from Texas and the aircraft was carrying a load consisting of six fuel drums according to a Campeche daily newspaper. The Learjet 25D was flying at a very low altitude, maybe in an attempt to land, when it crashed and burned in an open field located in Champotón, some 40 km south of Campeche. Both crew members were killed. Illegal flight suspected.

The airline transport pilot was conducting a cross-country repositioning flight. While en route to the destination airport, the pilot contacted air traffic control and stated that he was beginning to descend. No further radio transmissions were made by the pilot. Radar and GPS information showed, about the same time as the pilot's last transmission, the airplane's flightpath began descending in a westerly direction. The last recorded GPS point showed the airplane about 200 ft southwest of the initial impact point, 90 ft above ground level, and at a groundspeed of 66 knots. The airplane wreckage was located in an open field and impact signatures were consistent with a stall/spin, which had resulted in a near-vertical impact at a slow airspeed. The right propeller blades were found in the feathered position. Examination of the right engine found that the oil gauge housing extension was improperly secured to the oil gauge housing, which resulted in a loss of engine oil. Additionally, the examination revealed a hole in the right engine's crankcase, metal material in the oil sump, and signatures consistent with the lack of lubrication. Cockpit switches were positioned in accordance with the in-flight shutdown of the right engine. No anomalies were found with the left engine or airframe that would have precluded normal operation. Another pilot who had flown with the accident pilot reported that the pilot typically used the autopilot, and the autopilot system was found with the roll, heading, and pitch modes active. During the descent, no significant changes of heading were recorded, and the direction of travel before the stall was not optimal for the airplane to land before a fence line. It is likely that the autopilot was controlling the airplane's flightpath before the stall. Despite one operating engine, the pilot did not maintain adequate airspeed and exceeded the airplane's critical angle-of-attack (AOA), which resulted in an aerodynamic stall/spin. Correcting the last GPS recorded airspeed for prevailing wind, the airplane's indicated airspeed would have been about 72 knots, which is above the airplane's 0-bank stall speed, but an undetermined mount of bank would have been applied to maintain heading, which would have accelerated the stall speed. It could not be determined why the pilot did not maintain adequate airspeed or notify air traffic controller of an engine problem. Although a review of the pilot's medical records revealed that he had several historical medical conditions and the toxicology tests detected several sedating allergy medications in his system, it was inconclusive whether the medical conditions or medications impaired the pilot's ability to fly the airplane or if the pilot was incapacitated. It is also possible that the pilot was distracted by the loss of oil from the right engine and that this resulted in his failure to maintain adequate airspeed, his exceedance of the airplane's critical AOA, and a subsequent stall/spin; however, based on the available evidence, the investigation could not determine the reason for the pilot's lack of corrective actions.

The pilot was engaged in an agricultural spraying mission. In unknown circumstances, the single engine aircraft impacted terrain and came to rest against a small hill in Mount Linton. The aircraft was damaged beyond repair and the pilot, sole aboard, was seriously injured.

The private pilot was conducting a personal cross-country flight. The pilot reported that, during cruise flight at 6,000 ft mean sea level, he observed a crew alerting system oil pressure message, followed by a total loss of engine power. An air traffic controller provided vectors to a local airport; however, the pilot reported that the airplane would not reach the runway. He did not attempt to restart the engine. He feathered the propeller and placed the power lever to "idle" and the condition lever to "cut off." The pilot subsequently attempted a forced landing to a sports field with the gear and flaps retracted. The airplane collided with trees and the ground and then came to rest upright. Examination of the engine revealed that it displayed contact signatures to its internal components and evidence of ingested unburned organic debris, consistent with the engine likely being unpowered and the engine gas generator and power sections wind-milling at the time of impact. No evidence of any preimpact mechanical anomalies or malfunctions to any of the engine components was found that would have precluded normal operation. Recorded GPS flight track and systems data showed that the loss of engine power was preceded by about 5 minutes of flight on a constant heading and altitude with an excessive lateral g force of about 0.17 g and a bank angle between about 8 and 10 degrees, consistent with a side-slip flight condition. The airplane then entered a right turn with the autopilot engaged, and it lost power at the end of the turn. The data indicated that, even though the autopilot was engaged, the lateral g forces increased as the airplane leveled off and accelerated, indicating that the automatic rudder trim feature of the yaw damper system was not engaged. Given that the yaw damper system operated normally after the flight, it is likely that the pilot inadvertently and unknowingly disengaged the yaw damper during flight with the autopilot engaged. During a postaccident interview, the pilot stated that he was not aware of a side-slip condition before the loss of engine power. Although the fuel tank system was designed to prevent unporting of the fuel lines during momentary periods of uncoordinated flight, it was not intended to do so for extended periods of uncoordinated flight. Therefore, the fuel tank feed line likely unported during the prolonged uncoordinated flight, which resulted in the subsequent loss of engine power. If the pilot had recognized the side-slip condition, he could have returned to coordinated flight and prevented the engine power loss. Also, once the airplane returned to coordinated flight, an engine restart would have been possible.

En route from Anaco to Santa Bárbara del Zulia, the twin engine aircraft crashed in unknown circumstances by a wooded area located near Casigua El Cubo. The aircraft was destroyed by a post crash fire and all three occupants were killed. It is believed that the aircraft was engaged in an illegal contraband flight.

The aircraft departed Mwanza Airport at 1926LT on a cargo flight Nairobi. While passing FL169, the aircraft entered an uncontrolled descent. It passed FL146 at an excessive speed of 430 knots and eventually crashed in an open field located near Kogatende. The wreckage was found the following morning. The aircraft disintegrated on impact and all three occupants were killed.

The single engine aircraft departed Cannes-Mandelieu Airport at 1040LT bound for Courtrai-Wevelgem Airport, Belgium, with four passengers and one pilot on board. About one hour and 40 minutes into the flight, while cruising in IMC conditions at FL240, the aircraft start a quick descent to the right until FL149. Speed increased and the overspeed warning sound came on. Forty-five seconds after the start of the quick descent, the airplane initiated a climb with a rate of 10,000 feet per minute until it stalled at FL201, still in IMC conditions. The airplane then entered a dive and went into a flat attitude when it went out of clouds at an altitude estimated between 1,000 and 2,000 feet. This altitude was insufficient to the pilot to regain control and without external visual references, he lost control of the airplane that crashed in a wooded area. The pilot and a passenger were killed while three other passengers were injured. The aircraft was destroyed.