Buenos Aires-Ezeiza-Ministro Pistarini

Wrong approach configuration on part of the crew who continued the approach above the glide following an erratic appreciation of the situation. This caused the aircraft to land too far down the runway at an excessive speed. At the time of the accident, the runway surface was wet and the wind was gusting from 240° at 30 knots.

Wrong approach configuration on part of the flying crew who continued the approach below the glide in reduced visibility. The crew failed to follow the approach checklist and to check instruments. Lack of visibility was a factor.

Loss of control following an engine failure.

It was determined that the crew continued the approach below minima weather conditions and below the glide, causing the airplane to struck obstacles on short final. The captain decided to go around after the impact with the ILS antenna but it was too late.

The investigating commission considered the causes of the accident to be as follows :
a) excessive concentration by the crew on the indications given by the Flight Director;
b) the crew erroneously operated the Flight Director equipment on a direct ILS approach;
c) as a result of a) above, the crew did not check the instruments, which indicated:
- descending below the minimum safety altitude;
- rate of descent greater than normal for an ILS approach;
- longitudinal attitude of the aircraft greater than normal for an ILS approach;
- position of the aircraft below the ILS glide path.

The conclusion set forth above is based on the fact that the electro-mechanical reverse safety device installed on the landing gear is so designed that whec the left landing gear strut is compressed it closes an electric circuit and frees the throttle lock. Therefore, the aircraft must touch down and roll for some distance in order to lose some lift through decrease in speed, The full weight of the aircraft is then on the landing gear and it is possible to move the levers manually and place the throttles into the proper position to reverse the propellers and then to give more throttle to gain more reverse thrust, All this requires some time and some ground roll distance after touchdown, which may or my not have some effect on the estimated distance for braking the aircraft or discontinuing the landing. The fact that the reverse lock safety system was inoperative was considered a deficiency in maintenance, even in the assumption that it had been intentionally so adjusted by the crew or during overhauls in the aviation workshops. The confirmed abnormality explains why in this particular case the levers could be moved back and the propeller reversing system operated. In accordance with the above findings and conclusions, it was considered that the statements by the crew members should be disregarded because, as brought out by the evidence, the accident was due to premature operation of the reversing system, when the aircraft was on final approach at a height of 20 metres, thereby causing it to go into a stall, This, together with the fact that the reverse safety mechanism was not: operating as it should have been, led to operation of the reversing system before the landing gear had made contact with the runway an essential requirement for operation of the propeller reversing system, barring any irregularities in the operation of the equipment. It is furthermore considered that the pilot-in-command acted incorrectly and imprudently in prematurely operating the propeller reversing system during the final approach instead of following the required procedure of applying reverse propellers during the landing run, when the weight of the aircraft is firmly on the landing gear. Consequently, the accident -- which was classified as serious -- was attributed to sudden loss of lift of the aircraft when it was about to land, which caused it to drop to the ground, slew round and turn over as a result of premature application of the propeller reversing system. An unofficial report stated that a paper cup was placed on the center console by the crew. On final approach, the content of this cup poured on the gear levers, causing an electrical short-circuit that caused the activation of the thrust reversers.

The accident was caused by lack of discipline on the part of the pilot-in- command of the aircraft who did not follow the instructions of the flight plan or those relating to crossing the mountains.

It was determined that the wings were contaminated with frost and that the airplane has not been deiced prior to takeoff.

The aircraft disintegrated in flight due to rupture of the right wing following the application of loads in excess of the design loads, in a zone of extremely violent turbulence. A contributing factor was insufficient evaluation of the forecast, by both the aircraft captain and by the airline dispatcher, which resulted in the choice of an inappropriate flight altitude.

Wrong approach configuration on part of the pilot-in-command who continued the descent at an unsafe altitude (below the glide) and misjudged the distance with the ground.