Flight Details
Flight AR-527/03 was a scheduled domestic service from Mendoza to Buenos Aires Aeroparque, Argentina, with an intermediate stop at Pajas Blancas Airport. The flight plan was prepared in Mendoza by the airline's dispatcher and approved by the chief of the Operations Office and the Northwest Regional Control Area. The aircraft was cleared to fly at 8700 meters with reporting points along the airway at Chanar-Pampa Salinas and at the entrance to the Terminal Area.
Approach Sequence
The aircraft departed Mendoza at 1750 hours and first contacted Pajas Blancas control tower at 1840 hours. Six minutes later, it was cleared for an instrument approach to runway 17. The approach began at a height of 1500 meters, contrary to the regulation height of 3300 meters prescribed for jet aircraft. The outbound track was flown on a magnetic heading of 40 degrees, with the aircraft above the cloud layer at 1054 meters above ground. After the time specified in the airline's approach chart elapsed, a left-hand turn was initiated to intercept QDM 200 degrees. During the turn, altitude was maintained with landing gear extended, flaps at 20 degrees, and indicated airspeed of 140 knots.
On completing the turn, a magnetic heading of 200 degrees was flown toward the beacon, and the aircraft descended until intercepting VOR radial 168. At that point, the pilot believed he was 250 meters above ground. Continuing on instruments, he intercepted the VOR and changed course to 170 degrees. When visual contact with the runway was not established at 150 meters, he began a go-around, climbing on a magnetic heading of 105 degrees. He then initiated a right-hand turn to re-intercept the radio beacon and requested another clearance from the tower for another approach.
Second Approach and Impact
The pilot flew over the beacon at 1050 meters, then followed a magnetic heading of 40 degrees for about 2 minutes 30 seconds. While descending, he began a left-hand turn until obtaining QDM 200. The landing gear was extended and locked, flaps set to 20 degrees, and a normal descent at 500 feet per minute was maintained. He intercepted VOR radial 168, announced he was at 160 meters, and then initiated a turn to align with runway 17. Shortly thereafter, the aircraft's port wing struck trees five meters high, and the port landing gear contacted the ground. The pilot-in-command reduced power and pushed the control column forward. The aircraft traveled approximately 60 meters on its port landing gear, then rolled on all its undercarriage for another 700 meters. At 390 meters from the initial impact, the port wing struck more trees, the fuel tanks ruptured, and a fire broke out. The aircraft then struck the General Belgrano Railway tracks, breaking its undercarriage and tearing away 25 meters of rails, finally coming to rest 280 meters before the threshold of runway 17.
Official Cause
The probable cause, as determined by the investigation, was striking the ground during final approach when the pilot failed to execute the approved instrument entry procedure.