Cessna 207 Skywagon/Stationair

The pilot departed on a postmaintenance test flight during day visual meteorological conditions. According to the operator, the purpose of the flight was to break in six recently installed engine cylinders, and the flight was expected to last 3.5 hours. Recorded automatic dependent surveillance-broadcast data showed that the airplane was operating at altitudes of less than 500 ft mean sea level for the majority of the flight. The data ended about 3 hours after takeoff with the airplane located about 23 miles from the accident site. There were no witnesses to the accident, which occurred in a remote area. When the airplane did not return, the operator reported to the Federal Aviation Administration that the airplane was overdue. Searchers subsequently discovered the fragmented wreckage submerged in a swift moving river, about 40 miles southeast of the departure/destination airport. Postmortem toxicology tests identified 21% carboxyhemoglobin (carbon monoxide) in the pilot's blood. The pilot was a nonsmoker, and nonsmokers normally have no more than 3% carboxyhemoglobin. There was no evidence of postimpact fire; therefore, it is likely that the pilot's elevated carboxyhemoglobin level was from acute exposure to carbon monoxide during the 3 hours of flight time before the accident. As the pilot did not notify air traffic control or the operator's home base of any problems during the flight, it is unlikely that he was aware that there was carbon monoxide present. Early symptoms of carbon monoxide exposure may include headache, malaise, nausea, and dizziness. Carboxyhemoglobin levels between 10% and 20% can result in confusion, impaired judgment, and difficulty concentrating. While it is not possible to determine the exact symptoms the pilot experienced, it is likely that the pilot had symptoms that may have been distracting as well as some degree of impairment in his judgment and concentration. Given the low altitudes at which he was operating the airplane, he had little margin for error. Thus, it is likely that the carbon monoxide exposure adversely affected the pilot's performance and contributed to his failure to maintain clearance from the terrain. According to the operator, the airplane had a "winter heat kit" installed, which modified the airplane's original cabin heat system. The modification incorporated an additional exhaust/heat shroud system designed to provide increased cabin heat during wintertime operations. Review of maintenance records revealed that the modification had not been installed in accordance with Federal Aviation Administration field approval procedures. Examination of the recovered wreckage did not reveal evidence of any preexisting mechanical anomalies that would have precluded normal operation of the airplane. Examination of the airplane's right side exhaust/heat exchanger did not reveal any leaks or fractures that would have led to carbon monoxide in the cabin. Because the left side exhaust/heat exchanger was
not recovered, it was not possible to determine whether it was the source of the carbon monoxide.

The single engine aircraft departed Bucaramanga-Palonegro Airport on a charter flight to Málaga-Jerónimo de Aguayo Airport, carrying six passengers and one pilot. En route, the aircraft started a descent then a turn to the left when it impacted the slope of a mountain and crashed near Piedecuesta. The wreckage was found the following day and all seven occupants were killed. There was no fire.

The single engine aircraft departed Lima-Callao-Jorge Chávez Airport bound for Pisco. While cruising in foggy conditions east of Lima, the airplane collided with a mountain located between La Molina and Villa Maria del Triunfo. The wreckage was found in the evening, around 1840LT, and all three occupants were killed.

During a local sightseeing flight, the pilot noticed that the engine had lost partial power, and he initiated a turn back toward the airport while troubleshooting the loss of power. Despite the pilot's attempts, the engine would not regain full power and was surging and sputtering randomly. The pilot entered the airport's traffic pattern on the downwind leg, and, while on final approach to the runway, the airplane encountered multiple downdrafts and wind gusts. It is likely that, due to the downdrafts and the partial loss of engine power, the pilot was not able to maintain airplane control. The airplane subsequently landed hard short of the runway surface and nosed over, coming to rest inverted. The reported wind conditions around the time of the accident varied between 20 and 70 degrees right of the runway heading and were 14 knots gusting to greater than 20 knots. In addition, a company pilot who landed about 8 minutes before the accident reported that he encountered strong downdrafts and windshear while on final approach to the runway and that he would not have been able to reach the runway if he had a partial or total loss of engine power. Postaccident examination of the airframe and engine revealed no evidence of any preexisting mechanical malfunctions or failures that would have precluded normal operation. The engine was subsequently installed on a test stand and was successfully run through various power settings for several minutes. The reason for the partial loss of engine power could not be determined.

The pilot reported that he performed the takeoff with the airplane at gross weight and with the flaps up and the engine set for maximum power, which he verified by reading the instruments. During the takeoff, the airplane accelerated and achieved liftoff about 65 to 70 mph and then climbed a couple hundred feet before the pilot began to lower the nose to accelerate to normal climb speed (90 to 100 mph). The airplane then stopped climbing and would not accelerate more than 80 mph. While the pilot attempted to maintain altitude, the airplane decelerated to 70 mph with the engine still at the full-power setting. With insufficient runway remaining to land, the pilot made a shallow right turn toward lower terrain and subsequently made a hard landing in a field. The pilot likely allowed the airplane to climb out of ground effect before establishing a proper pitch attitude and airspeed for the climb, which resulted in the airplane inadvertently entering a “region of reversed command” at a low altitude. In this state, the airplane may be incapable of climbing and would require either more engine power or further lowering of the airplane’s nose to increase airspeed. Because engine power was already at its maximum and the airplane was at a low altitude, the pilot was unable to take remedial action to fly out of the region of reversed command.

The crew was completing a training mission. In unknown circumstances, the single engine aircraft crashed in a prairie located near Mount Nicholas, between Queenstown and Te Anau, coming to rest upside down. Both pilots were seriously injured and the aircraft was destroyed.

The Sandy Lake Seaplane Service Cessna 207, registration C-GHKB, was departing Island Lake, Manitoba, for St. Theresa Point, Manitoba, a VFR flight of about 7 miles. The aircraft departed runway 30 at 14:55 CDT and began a left turn about 300 feet. agl for a landing on runway 22 at St. Theresa Point. Almost immediately the aircraft entered white-out conditions in snow and blowing snow. The pilot was not IFR rated but attempted to stop the rate of descent that he noticed on the VSI. As the nose was pulled up the aircraft flew into the snow covered lake. There was no fire and the pilot was not injured. The pilot attempted to call FSS at 14:58 CDT. Communications were not established but FSS detected an ELT signal in the background of the transmission. The RCMP was notified and the pilot was rescued by snowmobile at 15:37 CDT. Company owner contacted Custom Helicopters and they dispatched two helicopters to pick up the downed pilot. Custom Helicopter was able to rescue the pilot and fly him to Island Lake nursing station. Pilot was shaken but otherwise uninjured.

The single engine aircraft was engaged in skydiving flights at Clinceni Airport. Shortly after takeoff, while climbing to a height of about 200 feet, the engine failed. The pilot attempted an emergency landing when the aircraft crash landed in a field located 300 meters past the runway end. A skydiver was slightly injured while three other occupants were unhurt. The aircraft was damaged beyond repair.

The pilot departed on a positioning flight during dark night, marginal visual meteorological conditions. A witness, who was waiting for the airplane at the destination airport, stated that shortly after the pilot-controlled airport lighting activated, a snow squall passed over the airport, greatly reducing the visibility. The accident airplane never arrived at its destination, and a search was initiated. The airplane’s fragmented wreckage was discovered early the next morning in a wooded area, about 2 miles from its destination. A review of archived automatic dependent surveillance-broadcast (ADS-B) data received from the accident airplane showed that the pilot departed, and the airplane climbed to about 700 feet above ground level. The airplane remained at about 700 feet for about 3 minutes, and then entered a shallow right-hand descending turn, until it impacted terrain. On-site examination of the airplane and engine revealed no preaccident mechanical anomalies that would have precluded normal operation. The cockpit area was extensively fragmented, thus the validity of any postaccident cockpit and instrument findings was unreliable. Likewise, structural damage to the airframe precluded the determination of flight control continuity. A postaccident examination of the engine and recovered components did not disclose any evidence of a mechanical malfunction. Given the witness account of worsening weather conditions at the airport just before the accident and the lack of mechanical anomalies with the airplane, it is likely that the accident pilot encountered heavy snow and instrument meteorological conditions while approaching the airport. It is also likely that the pilot became spatially disoriented during the unexpected weather encounter and subsequently collided with terrain.

The pilot departed on a scheduled commuter flight at night from an unlit, rough and uneven snow-covered runway with five passengers and baggage. During the takeoff roll, the airplane bounced twice and became airborne, but it failed to climb. As the airplane neared the departure end of the runway, it began to veer to the left, and the pilot applied full right aileron, but the airplane continued to the left as it passed over the runway threshold. The airplane subsequently settled into an area of snow and tundra-covered terrain about 100 yards south of the runway threshold and nosed over. Official sunset on the day of the accident was 48 minutes before the accident, and the end of civil twilight was one minute before the accident. The Federal Aviation Administration's (FAA) Airport/Facility Directory, Alaska Supplement listing for the airport, includes the following notation: "Airport Remarks - Unattended. Night operations prohibited, except rotary wing aircraft. Runway condition not monitored, recommend visual inspection prior to using. Safety areas eroded and soft. Windsock unreliable." A postaccident examination of the airplane and engine revealed no mechanical anomalies that would have precluded normal operation. Given the lack of mechanical deficiencies with the airplane's engine or flight controls, it is likely the pilot failed to maintain control during the takeoff roll and initial climb after takeoff.