Bismarck

The pilot and two medical crewmembers were repositioning the airplane to pick up a patient for aeromedical transport. Dark night instrument meteorological conditions prevailed for the flight. Radar data showed the airplane climb to 14,000 ft mean sea level after departure and proceed direct toward the destination airport before beginning a right descending turn. The airplane subsequently broke up inflight and impacted terrain. No distress calls were received from the pilot before the accident. Although weather conditions were conducive for inflight icing, no evidence of structural icing was identified at the scene. The debris field was 2,500 ft long and the disbursement of the wreckage confirmed that both wings, the horizontal stabilizer, both elevators, and both engines separated from the airplane before impacting the ground. Examination of the wreckage revealed that the initiating failure was the failure of the wing where it passed through the center of the airplane. The three wing spars exhibited S-bending deformation, indicative of positive overload producing compressive buckling and fracture. Further, impact signatures as black paint transfers and gouged aluminum, were consistent with the left outboard wing separating when it was struck by the right engine after the wing spars failed. There was no evidence of any pre-exiting conditions that would have degraded the strength of the airplane structure at the fracture locations. Flight control continuity was confirmed. An examination of the engines, propellers, and available systems showed no mechanical malfunctions or failure that could have contributed to the accident. The descending right turn was inconsistent with the intended flight track and ATC-provided clearance. However, there was insufficient information to determine how it was initiated and when the pilot became aware of the airplane's state in the dark night IMC conditions. Yet, the
absence of a distress call or communication with ATC about the airplane's deviation suggests that the pilot was not initially aware of the change in state. The structural failure signatures on the airplane were indicative of the wings failing in positive overload, which was consistent with the pilot initiating a pullup maneuver that exceeded the airplane spars' structural integrity during an attempted recovery from the spiral dive.

The aircraft disappeared from ATC radar immediately after being cleared to descend from 12,000 feet to 10,000 feet. ATC radar data showed the aircraft at 11,900 to 12,000 feet for approximately the last 6 minutes prior to the disappearance, with the last Mode C altitude and discrete transponder code 2402 (at 0221:03) reported as 11,800 feet. The last three returns, 12,000, 11,900, and 11,800, are consistent with the start of a descent from 12,000 feet. Due to construction at the radar antenna site, the area where the aircraft disappeared was blocked from radar coverage. Subsequent attempts by the controller to contact the aircraft were unsuccessful. A 7,000- to 7,500-foot overcast was reported at the destination, along with lower clouds and precipitation. Documentation at the accident site indicated an approximate level flight path from the broken treetops to the area of ground impact into a northwest-facing 60-degree mountain slope at approximately the 5,600-foot level. The wreckage was not located for approximately two months. Post-accident examinations of the aircraft's Bendix/King KEA130A (United Instruments 5035PB-P57) encoding altimeter revealed needle impressions on the indicator face and pointers consistent with an altitude indication of 12,620 feet. The internal components of the unit were severely damaged and a functional test was not possible. The aircraft was equipped with a copilot's altimeter. Only the faceplate was recovered and examined. One impression on the main faceplate revealed a needle impression by the 100-foot pointer consistent with 560 feet. The position of the 1,000-foot pointer could not be determined. The pilot's 4-day activity history showed that he was returning from a demanding 3-day work assignment, that his recent sleeping schedule was irregular, and that he had been awake about 20 hours at the time of the accident. There was no evidence found of a mechanical failure or malfunction at the time of the accident.

The airplane was making an instrument landing system approach in instrument meteorological icing conditions when control was lost. The airplane impacted the terrain 1.6 miles from the approach end on the runway. The airplane contacted the terrain with the left wing first prior to cartwheeling and coming to rest approximately 120 feet from the point of first impact. The pilot had 19 hours total flight time in Cessna 208's of which 1.9 hours were in actual instrument meteorological conditions.

While on a night approach to Bismarck Airport on a cargo flight from Dickinson, the pilot failed to realize his altitude was too low when the twin engine airplane struck power cables, lost height and crashed in an open field located few miles short of runway. The aircraft was destroyed and the pilot was seriously injured.

While cruising by night on a cargo flight from Jamestown to Bismarck, the pilot, a full time student, fell asleep. Under autopilot, the twin engine airplane continued for a while before sticking a mountain located in the region of Bismarck. The aircraft was destroyed and the pilot was seriously injured.

After touchdown, the crew was unable to stop the aircraft within the landing distance available. The aircraft overrun, rolled for several yards and collided with construction equipment before coming to rest in flames. Both pilots and a passenger were killed while all other occupants were injured. Delivered to Northwest Airlines in June 1939, the aircraft was destroyed.