Accident
Aerolíneas Argentinas Flight 670 departed Ministro Pistarini International Airport in Buenos Aires at 3:54 PM on 8 December 1957, bound for San Carlos de Bariloche International Airport. The aircraft carried 6 crew and 55 passengers. Air traffic control cleared the flight for an IFR route outside airways at an altitude of 3,937 feet (1,200 m) toward Neuquén, with the remainder of the flight cleared for 7,874 feet (2,400 m).
Contrary to its clearance, the aircraft flew at an altitude of 328 to 492 feet (100–150 m) for approximately 35–40 km (22–25 mi), deviating 21 km (13 mi) from its intended course. The captain adopted this low-level tactic to avoid an intense cold front by flying beneath it. The captain then flew into the most active part of the worsening storm and initiated a sharp climb. At 8,202 feet (2,500 m), the left wing failed, followed by the tail section, and the aircraft entered an uncontrollable dive.
At 4:45 PM, Flight 670 crashed 25 km (16 mi) southeast of San Carlos de Bolívar. The impact occurred at a descent angle of 35 degrees with a 25-degree left bank and a speed exceeding 400 km/h (250 mph). The aircraft was destroyed by impact and post-crash fire. None of the 61 occupants survived.
Aircraft
The Douglas DC-4, registration LV-AHZ (msn 27227), was built in 1944 for the U.S. Air Force. It remained in military service until March 1946, when it was sold to United Airlines. The aircraft was withdrawn from service in January 1957 and subsequently sold to Aerolíneas Argentinas in May 1957, where it operated until the accident.
Investigation and Aftermath
The investigation determined that the aircraft disintegrated in flight due to the separation of the left wing and tail section. This structural failure resulted from stresses induced by severe turbulence encountered in harsh weather conditions. The pilot’s decision to fly recklessly into the storm was noted as a contributing factor.