Mitsubishi MU-2 Marquise

The flight departed on a maintenance test flight with known wind gusts to 27 knots. Before takeoff the pilot performed an NTS check to each engine with no discrepancies noted. During flight the pilot performed an NTS check to the left engine. Two attempts to restart the left engine were unsuccessful. Each time the propeller came out of the feathered position and started to rotate but there was no fuel flow or ignition. The flight returned to land and while on short final to runway 29 with the wind from 250 degrees at 20 knots, a witness observed the airplane pitch nose up then down then heard the sound of power applied to the right engine. The airplane than rolled to the left, pitched nose down, impacted the ground coming to rest nearly inverted with the wing section separated. Postaccident examination of the left engine and accessories revealed no evidence of preimpact failure or malfunction. The left engine fuel shutoff valve was found in the 'closed' position and no fuel was found aft of the fuel shutoff valve. The pilot stated that he has no recollection of the accident. The left and right engines had just been installed following 'hot section' work to both, and both were then started the day after installation with no discrepancies noted by company maintenance personnel.

A Mitsubishi MU-2 departed Salt Lake City, Utah, and climbed to 16,000 feet MS on an IFR flight to Pocatello, Idaho. While in cruise flight, the MU-2 encountered structural icing conditions. According to radar data, the MU-2 began slowing from a cruise speed of about 190 knots with slight deviations from heading and altitude. The airspeed decreased to about 100 knots, and the flight crew declared an unspecified emergency, then radio contact was lost. The MU-2 began a right turn, then it entered a steep descent and crashed. The pilot of a Beech 1900 (about 12 minutes in trail of the MU-2), stated that he encountered moderate rime icing at 16,000 feet. The Beech pilot activated his deice boots (3 times) and descended to 12,000 feet to exit the icing conditions. The MU-2 flight manual warned that during flight in icing conditions, stall warning devices may not be accurate and should not be relied upon; and to minimize ice accumulation, maintain a minimum cruise speed of 180 knots or exit the icing conditions. An investigation determined that the captain of the MU-2 was aware of deficiencies in the timer for the deice boots, as well as other maintenance deficiencies. The captain's medical certificate was dated 11/17/94; he was providing executive transportation for compensation under an agreement for "contractual flights," under 14 CFR 91. Although icing conditions were forecast in the destination area, no icing was forecast for the en route portion of the flight.

A witness stated he observed the airplane on climbout from runway 32. The airplane started a right turn estimated at about 30 to 45° angle of bank. The airplane stopped climbing and began descending. Subsequently, it collided with a tree line, while in a right bank, and then it impacted the ground. Weather conditions at the time of accident were described by the witness as very dark, with no ambient light or visible horizon. Examination of the airframe, flight control system, engine assembly, and propeller assembly revealed no evidence of a precrash failure or malfunction. The autopilot was found in the off position, and the autopilot circuit breakers were not tripped. The pilot and passenger were seriously injured and had no memory of the flight. A radio transcript revealed that after taking off, the flight had made one radio transmission to request an ifr clearance.

The twin engine aircraft was completing a cargo flight from Neuquén to Buenos Aires-Ezeiza Airport with an intermediate stop in Bahía Blanca, carrying two pilots on behalf of Encotesa. Shortly after departure from Neuquén-Juan Domingo Perón Airport, while climbing by night, the crew informed ATC about his ETA in Bahía Blanca when control was lost. The aircraft crashed in Chimpay, in the suburb of Neuquén, about 4 km northeast of the airport, bursting into flames. Both pilots were killed.
Crew:
Horacio Ovidio Filippini, pilot,
Valerio Augusto Diehl, pilot.

The aircraft departed Sydney for Melbourne International airport at 0130 on 21 December 1994. En-route cruise was conducted at flight level 140. Melbourne Automatic Terminal Information Service (ATIS) indicated a cloud base of 200 feet for the aircraft's arrival and runway 27 with ILS approaches, was in use. Air Traffic Control advised the pilot of VH-UZB, another company MU2 that was also en-route from Sydney to Melbourne, and the pilot of VH-IAM while approaching the Melbourne area, that the cloud base was at the ILS minimum and that the previous two aircraft landed off their approaches. VH-UZB was slightly ahead of VH-IAM and made a 27 ILS approach and landed. In response to an inquiry from the Tower controller the pilot of VH-UZB then advised that the visibility below the cloud base was 'not too bad'. This information was relayed by the Tower controller to the pilot of VH-IAM, who was also making a 27 ILS approach about five minutes after VH-UZB. The pilot acknowledged receipt of the information and was given a landing clearance at 0322. At 0324 the Approach controller contacted the Tower controller, who had been communicating with the aircraft on a different frequency, and advised that the aircraft had faded from his radar screen. Transmissions to VH-IAM remained unanswered and search-and-rescue procedures commenced. Nothing could be seen of the aircraft from the tower. A ground search was commenced but was hampered by the darkness and reduced visibility. The terrain to the east of runway 27 threshold, in Gellibrand Hill Park, was rough, undulating and timbered. At 0407 the wreckage was found by a police officer. Due to the darkness and poor visibility the policeman could not accurately establish his position. It took approximately another 15-20 minutes before a fire vehicle could reach the scene of the burning aircraft. The fire was then extinguished.

The crew was engaged in a post maintenance test flight. En route, the copilot informed ATC about technical problems when control was lost. The aircraft entered a dive and crashed in the sea off Hamamatsu. All four crew members were killed.

The day prior to the accident, both propellers have been changed at Basel Airport and the pilot returned to his base in Zurich. Due to poor weather conditions en route, he was unable to conduct a test of both propellers, reason why a test flight was scheduled on September 3. After his departure from Zurich-Kloten Airport runway 28, the pilot flew to the east and was cleared to climb to FL130, the assigned altitude where the test should be performed. Ten minutes after takeoff, he informed ATC that he would shut the right engine down. The aircraft lost speed and height then deviated from the prescribed flight path. The pilot was able to restart the right engine and to regain control when, three minutes later, he informed ATC he would shut the right engine down for the second time. The aircraft entered a right turn then a rapid descent and crashed in a wooded area, bursting into flames. The aircraft was destroyed and the pilot, sole on board, was killed.

The aircraft was completing an ambulance flight from Rarotonga (Cook Islands) to Tahiti, carrying to Australian patients, two doctors and one pilot. On final approach to Papeete-Faaa Airport runway 04 by night, the twin engine aircraft descended too low and crashed in the sea about 6,4 km short of runway. The pilot did not send any distress call prior to impact and the aircraft struck the water surface in a flat attitude. All five occupants were killed. For unknown reasons, the pilot failed to realize his altitude was insufficient on short final. The lack of visibility and visual references were considered as contributing factors.

The pilot reported the right engine failed, followed by the left engine approximately one minute later while he was in cruise at 25,000 feet. He said he initiated a steep descent to get below 18,000 feet, and attempts at restarting the left engine were unsuccessful. The pilot landed 500 feet down a 1,900 feet long runway and ran off the departure end, 300 feet, into a wooded area. Post accident investigation found 130 gallons of fuel onboard in the main tanks. The fuel was tested and found to be free of water. The fuel lines were free of obstructions and the fuel pumps worked. A failed torque sensor was found on the left engine which would disconnect the left engine driven fuel pump. The right engine was test run satisfactorily.

While cruising at FL240, a propeller (prop) hub arm on the left prop failed, releasing the prop blade, which struck a 2nd blade, breaking off its tip. This resulted in a severe engine vibration and shutdown of the left engine. The left engine was forced downward and inboard on its mounts. The cabin depressurized, possibly from blade contact. The flight crew made an emergency descent and received a vector to divert for an ILS approach to Dubuque. The airplane was incapable of maintaining altitude and descended in instrument conditions. Subsequently, it collided with a silo and crashed about 8 miles south of Dubuque. An investigation revealed the left prop hub failed from fatigue that initiated from multiple initiation sites on the inside diameter surface of the hole for the pilot tube. There was evidence that the fatigue properties of the hub were reduced by a combination of factors, including machining marks or scratches, mixed microstructure, corrosion, decarburization, and residual stresses. All eight occupants were killed, among them George Mickelson, 52, Governor of South Dakota.