Oklahoma

The pilots of Mitsubishi MU-2, N106MA, and a Cessna 310 with no registration number elected to fly in formation at night, though neither pilot had formal training in formation flying nor experience in night formation. They joined up in flight and the MU-2 pilot was flying on the wing of the Cessna 310. The MU-2 pilot communicated that he was going to change positions from the right side to the left side of the 310C. The Cessna 310 pilot and his passenger lost sight of the MU-2 when it dropped back to a position in the rear of the Cessna 310. Soon thereafter, the two aircraft collided and the MU-2 went out of control and crashed. The right horizontal stabilizer was torn from the Cessna 310 and the 310's empennage, right wing and props were damaged, but it was landed without injury to its occupants. An investigation revealed the tail light of the Cessna 310 was inoperative. Sole on board, the pilot was killed.

Airplane was departing on a required maintenance test flight following replacement of both engines. Witnesses stated that the takeoff roll and initial climb appeared normal, but that at about 500 feet agl, the airplane entered a right bank which continued until the wings were vertical and the nose fell through. Airplane impacted in an inverted steep nose down attitude. Examination of wreckage revealed that the right engine had been secured and feathered. Subsequent investigation did not reveal any evidence of pre-impact failure or malfunction of either engine or any of the airframe systems. Engine mounting/rigging continuity could not be established due to impact damage. The pilot was a principal in the operator's organization and not one of the regular line pilots. Evidence indicated that the gear was up and that the left spoiler was deployed at impact. Emerg procedure taught in transition training is to use rudder trim as soon as possible after engine failure to preclude deployment of spoilers. Rudder trim found in neutral position. All three occupants were killed.

A pilot (whose instrument currency could not be determined) took off at night in IMC. Shortly after takeoff, the aircraft crashed about 1.5 mile from the departure end of the runway. There was evidence that it impacted in an 85° right bank, nose down attitude at high speed. No preimpact part failure was found during the investigation; however, during a pre-purchase inspection on 10/16/90, several discrepancies were noted. These included an inop flight director, an autopilot malfunction and a misrigged flight control system that allowed the control wheel to indicate a left turn when the aircraft was in level flight. There was no record of these being repaired. Records showed the pitot-static system was last tested on 3/24/88. The pilot was taking sine-aid and tylenol for a chronic sinus infection. Although tox checks indicated the presence of 50.7 ug/ml of pseudoephedrine and 36.4 ug/ml of acetaminophen in the pilot's urine, none was found in his blood. The sinus cond could have affected the pilot's balance and equilibrium. All six occupants were killed.

The pilot did not hold a type rating or written authorization to act as pilot in command. The copilot did not hold a type rating or written authorization to act as second in command and his medical had expired. The aircraft did not have an airworthiness certificate nor had a special flight permit been issued. The left propeller went into reverse during the initial climb due to corrosion and deterioration of the wiring that controlled the propeller. The aircraft crashed out of control after colliding with power lines during takeoff. It struck the ground and went through a fence then down a slope and over an embankment. The aircraft then bounced across a street while turning around and colliding with a power line pole tail first. The aircraft had traveled about 537 feet from initial ground contact. All 3 engines were still producing power when the aircraft came to rest. Both occupants escaped uninjured.

The number one (left) engine failed during the takeoff from runway 35. It was reported that the aircraft yawed sharply left and climbed to between 50 and 100 feet agl before it began losing altitude. The aircraft struck the ground and continued to move forward on the ground several hundred feet until it struck the airport perimeter fence. The aircraft came to rest 1,600 feet west of the runway, on a heading of 290°. A post-crash fire destroyed the cargo area of the aircraft. Examination of the left engine revealed a compressor turbine blade airfoil separation. Disassembly of the propeller on the left engine indicated that the propeller had autofeathered normally after the engine failed. The captain reportedly made the takeoff. All eight occupants were injured, two seriously. The aircraft was damaged beyond repair.

The captain was cross-feeding both engines from the right tank while the first officer (f/o) was flying, without informing the f/o. The captain then left the cockpit while cross-feeding. Both tank valves and the right boost pump were on. The right tank ran dry, the right engine failed, and the prop autofeathered while the captain was absent. The captain returned, turned on the left boost pump, but left the right boost pump and the valves open, and attempted to restart the right engine. The left engine then failed but this was not recognized by the crew. The electrical system failed due to the attempted restarts and the fact that nonessential equipment was not turned off. The captain did not apply sufficient pull to the emergency gear handle to lower the gear manually. The aircraft was landed on a short wet sod runway, with the gear and flaps up, at a high rate of speed. The aircraft ran off the end of the runway, through a ditch, across a road, and into trees. Both pilots escaped uninjured.

The crew was performing a local training mission at Altus AFB. After landing, smoke spread in the cockpit and a fire erupted. The crew immediately stopped the aircraft and the runway and evacuated the cabin safely. There were no injuries while the aircraft was totally destroyed by fire.

Atr pilot departing airport under VMC experienced failure of the right engine shortly after lift-off. The aircraft yawed right followed by a steep right roll, contacting power lines with the right wing and subsequently impacted the ground. A post-crash fire destroyed the aircraft with the exception of both engines and a portion of the right wing panel. The engine failed due to lack of lubrication to the impeller shaft caused by blockage of oil jet due to fod. Oil line from scavenge sump to scavenge pump inlet had been replaced prior to accident. The aircraft had experienced maintenance problem (oil leak) approximately 2 weeks prior to accident. Source of fod is undetermined. Both occupants were killed.

An intermittent fire in the left engine accessory section led to loss of fuel to the engine. The right engine ingested water and quit. The landing gear had been left pinned in the down position because of a malfunction reported on the previous flight. Neither propeller was feathered, but the resulting high rate of descent led to a forced landing before the left tank blew up and the wing burned off. The aircraft was destroyed by fire after all three occupants escaped without serious injury. The aircraft was being ferried to another facility for restoration.

During an engine start, prior to the flight, the left engine backfired 2 or 3 times. A witness described the 1st backfired as 'the loudest I have ever heard.' When the aircraft took off, two persons living near the departure end of the runway noted that the aircraft (believed to be the same) sounded different and had a 'cluttering sound'. While climbing, the pilot declared an emergency and reported a fire in the left engine. He was vectored toward Altus AFB while descending in IFR conditions. He descended into VFR conditions and saw the airport about 3 miles away. A witness saw smoke and fire trailing from the vicinity of the left engine. He stated that the aircraft's nose came up, the plane rolled to the left, then it entered a steep, nose down, inverted attitude just before it crashed and burned. An exam revealed the engine exhaust manifold header assy had failed and allowed hot exhaust gases to escape in the engine nacelle in the vicinity of fuel and oil lines. Corrosion had progressed thru the header assy. Ad 75-23-08 requested general inspection, but contained note 'do not remove clamps.' No record of replacement in 6,100 hours. Both occupants were killed.