Takeoff (climb)

The aircraft was taking off on the final sowing sortie, after which the pilot was to return to home base. The pilot reported that, on the takeoff roll, the engine appeared to overspeed and that the aircraft failed to get airborne. It subsequently sank into a shallow gully off the end of the strip. After the accident, one propeller blade was found to be free to rotate about its feathering axis. Metallurgical analysis indicated that the pitch change knob on the subject blade failed as the result of ductile overload. A second pitch change knob was also bent and cracked but had not separated from the blade. The overload sustained by the pitch change knobs was determined to have occurred at impact, not in flight. No reason was established for the failure to become airborne.

The aircraft had been chartered to transport an airline crew of nine persons from Glasgow to Aberdeen. The aircraft was crewed by two pilots and, so far as could be determined, its take-off weight was between 8,320 and 8,600 lb. The maximum permitted take-off weight was 8,400 lb. ATC clearance for an IFR departure was obtained before the aircraft taxied from the business aviation apron for take-off from runway 23, with a take-off run available of 2,658 metres. According to survivors, the take-off proceeded normally until shortly after the aircraft became airborne when they heard a thud or bang. The aircraft was then seen by external witnesses at low height, to the left of the extended runway centerline, in a wings level attitude that later developed into a right bank and a gentle descent. Witnesses reported hearing an engine spluttering and saw at least one propeller rotating slowly. There was a brief 'emergency' radio transmission from the commander and the aircraft was seen entering a steep right turn. It then entered a dive. A witness saw the wings levelled just before the aircraft struck the ground on a northerly track. Three survivors were helped from the wreckage by a nearby farm worker before flames from a severe post-impact fire engulfed the cabin.

LAPA flight 3142 was scheduled to depart from Buenos Aires-Jorge Newbery Airport at 20:36 for a 1 hour and 15 minute flight to Córdoba, Argentina. The first officer and cabin crew were the first to arrive at the Boeing 737-200. The first officer notified one of the mechanics that the total fuel requirement was 8,500 kg, all to be stored in the wing tanks. The mechanic noticed there was still some fuel in the central tank and commenced transferring the fuel from the central to the wing tanks. At that moment the captain boarded the flight. He threw his paperwork on the ground, showing annoyance, confirming that attitude by later shutting off the fuel transfer between the main tank and the wing tanks. During their first four minutes on board, the captain, the co-pilot and the purser talked about trivial matters in good spirits, focusing on the purser's personal issues. When the purser left the cockpit, the conversation changed tone as they discussed a controversial situation about the family problems of the captain. The captain said that he was "going through bad times", to which the copilot replied that he was also having a bad day. Without interrupting the conversation, the crew began working the checklists, mixed with the personal issues that worried them and that led them to misread the checklist. In the process they omitted to select the flaps to the appropriate takeoff position. This confusing situation, in which the checklist procedure was mixed with conversation irrelevant to the crew's task, persisted during push back, engine start and taxiing, up to the moment of take-off, which was delayed by other aircraft waiting ahead of the LAPA flight and heavy arriving traffic. During this final wait, the crew members were smoking in the cockpit and continued their conversation. Take-off was started on runway 13 at 20:53 hours. During the takeoff roll the Take-off warning system sounded because the flaps had not been selected. The crew ignored the warning and continued the takeoff. After passing Vr, the pilot attempted to rotate the aircraft. The stick shaker activated as the aircraft entered a stall. It successively impacted the ILS antenna, the perimeter fence, a waiting shelter for buses, two automobiles, two excavators and an embankment where it stopped. Immediately a fire erupted. Three flight crew members, 60 passengers and two persons inside an automobile were killed.

The pilot had the main and auxiliary fuel tanks filled and performed an abbreviated preflight prior to departing the Alpine Airport. The pilot did not perform an engine run-up prior to takeoff. The pilot stated that while the airplane was climbing through 100 feet agl, the left engine 'started to surge.' The pilot reported that he knew the airplane would not be able to climb at field elevation with one engine inoperative. The pilot switched the left engine's boost pump from low to high; however, the left engine continued to surge while the airplane lost altitude. The pilot initiated a forced landing with the landing gear and flaps retracted and the left propeller unfeathered. The airplane impacted the ground left wing tip first and a fire erupted, which damaged the left wing and left side of the fuselage. The left engine's spark plugs were found covered with thick black soot. The left engine's magnetos were rotated using an electric hand-held drill, and the left magneto did not produce any spark and the right magneto produced a spark in three of its six distributor cap posts. The left magneto's primary winding resistance and capacitor leakage were found to be beyond the manufacturer's specified limits. The internal components of both magnetos were covered in a dark oil and debris. The maximum takeoff weight for the accident airplane was 6,350 pounds; however, the takeoff weight at the time of the accident was calculated to be 6,509 pounds. The aircraft's single engine performance charts indicated that the airplane would obtain a 29 fpm climb at maximum gross weight with the inoperative engine feathered. The pilot operating handbook's supplement section indicated that the auxiliary fuel pump should only be used when the engine-driven fuel pump failed. A caution statement states in bold print, 'If the auxiliary fuel pump switches are placed in the HIGH position with the engine-driven fuel pump(s) operating normally, total loss of engine power may occur.'

With an auxiliary fuel tank system installed, the pilot filled the tanks and departed. A few minutes later, he noticed fuel on the floor of the cabin, and tried to reach an airport. However, the fuel fumes were so strong he elected to land in an open field. After touchdown, the airplane passed through a ditch the pilot had not observed from the air. The nose landing gear collapsed and the airplane nosed over. An airborne witness reported the pilot exited the airplane after about 5 minutes, and about 5 minutes later, the airplane caught fire and burned. The post crash fire consumed the cabin. In an interview, the pilot reported that he had not initiated use of the auxiliary fuel tank system when the accident occurred. He also reported he could not see where the fuel was coming from. The investigation revealed the tank installation did not match the FAA Form 337, the instructions for use of the ferry tank system were inadequate, and the pilot had reported that the auxiliary fuel pumps were secured to a board which was not secured to the airplane.

During the takeoff roll on runway 20, the aircraft started to skid. Halfway down, the crew decided to abandon the takeoff procedure but the aircraft was unable to stop within the remaining distance. It overran and came to rest in a ravine. Both pilots escaped uninjured and the aircraft was damaged beyond repair. Weather conditions were good at the time of the accident with an OAT of 18° C. and light wind. The Surkhet Airport runway 20/02 is grass and is 3,400 feet long. It was reported that at the time of the accident, the turf was quit high and wet due to the morning dew which was considered as a contributing factor.

The airplane impacted the terrain approximately 2,065 feet south of the departure end of runway 22. Damage to the cockpit section of the wreckage indicated a nose down crush angle of approximately 80 degrees. The wreckage path was on a 208 degree heading, and the distance from the initial impact to the location of the empennage was about 142 feet. The cockpit and cabin were destroyed by post impact fire. Examination of the engines and propellers revealed no preexisting failures or conditions that would have prevented normal operation. The engines exhibited indications of rotation, and the witness marks on both sets of propellers were consistent with the propellers operating in the governing range at impact. Control continuity was established from the right aileron, elevator, and rudder. Witnesses reported the airplane seem to be operating normally during taxi and takeoff, but that it entered a steep left bank after clearing a 100 foot powerline located about 1,800 feet from the departure end of runway 22. After entering the steep left turn, the nose of the airplane dropped and the airplane impacted the ground. There was no evidence in the airplane's maintenance records of any annual maintenance inspection since August, 1997, although an airframe and powerplant mechanic reported that he had completed an inspection on June 30, 1999. There was no record in the airplane's maintenance records of compliance with five airworthiness directives applicable to the airplane.

The aircraft departed Tianjin on a cargo flight to Moscow with intermediate stops in Irkutsk and Perm, carrying a load of 49,750 kilos of various goods and seven crew members. At Irkutsk-Intl Airport, 38 tons of fuel were uplifted and the crew calculated 30,040 kilos for the cargo, giving a total weight of 170 tons, about 4 tons below the MTOW. During the takeoff roll, after a course of 2,000 metres, at a speed of 225 km/h, the captain started the rotation. The aircraft lifted up and flew for about 4 seconds when the captain requested gear up. At a speed of 250 km/h, the aircraft passed the runway end and adopted a 16° angle of attack. Then the aircraft' speed decreased when the flight engineer reduced the power on all four engines and activated the thrust reverser systems on both left engines n°1 and 2. The aircraft rolled to the left, collided with a building containing an electrical transformer and came to rest 1,476 metres past the runway end, bursting into flames. All seven occupants were injured, two seriously. The aircraft was destroyed.

During takeoff, the twin-engine airplane was observed to roll left, pitch nose down, and impact terrain shortly after the pilot reported to ATC that he had a problem. Witnesses reported that the left engine was producing black smoke during the takeoff roll. One witness stated that the airplane had slowed to approximately 60-70 mph prior to rolling to the left. A mechanic, who worked on the airplane prior to the accident, stated that the pilot reported being unable to maintain manifold pressure (MP) with the left engine. The mechanic found that the left engine's rubber interconnect boot, which routes induction air between the turbocharger controller elbow and the fuel servo, was 'gaping open.' The mechanic reseated the boot and tightened the clamp. The pilot flew the airplane and reported no problems. During a second flight, the pilot reported that the left engine was again unable to maintain MP. Prior to the accident flight, the pilot informed the mechanic that the 'hose had slid off again' and that it had been reinstalled and he 'felt sure it was o.k.' A witness stated that he saw the pilot working on the left engine the morning of the accident. At the accident site, the left engine's interconnect boot was found disconnected. The clamp securing the boot was not located. No other preimpact anomalies were found with the engines, propellers, turbochargers, or fuel servos.

The aircraft departed Kathmandu-Tribhuvan Airport on a cargo flight to Sharjah with an intermediate stop in New Delhi, carrying five crew members and a load of 21 tons of woolen carpets. After takeoff from runway 20, the crew continued to climb but failed to realize his altitude was insufficient. The aircraft struck the slope of Mt Champadevi located 11 km southwest of the airport and disintegrated on impact. All five crew members were killed.