The aircraft involved in the accident was a Boeing 737-2V2 Advanced, with Pratt & Whitney type JT8D-17 engines. It was manufactured in 1981 and made its first flight on June 11 of that year. When Boeing delivered it, it was registered as N8283V, but when it arrived in the TAME fleet in October of the same year, its registration changed to HC-BIG. The aircraft was named "Ciudad de Loja" upon its delivery to TAME. It was the only Boeing 737 ever operated by the airline. The plane was piloted by captain Jorge Peña and an unnamed first officer. 103 people came from Ecuador, 11 came from Colombia, and five from the United States.
Flight history
On the morning of 11 July 1983, the aircraft took off from Mariscal Sucre International Airport in Quito for a domestic flight to Mariscal Lamar Airport in Cuenca with 111 passengers and eight crew members. The aircraft encountered foggy conditions during the final approach to Mariscal Lamar Airport, but the weather conditions of that day were reported as clear. The crew contacted the Cuenca control tower for permission to land the plane, which was granted. During the final few minutes of the flight, the pilots were distracted during a conversation and didn't know that the plane was flying dangerously low towards a mountain. Also, at the same time, they were experimenting with some of the aircraft's controls and systems. Seconds before the plane hit the mountain and from the airport, the Ground Proximity Warning System activated, announcing an imminent terrain collision and sounding an alarm. The captain and first officer attempted to climb clear of the mountain by applying full power on the engines and making a steep climb, but it was too late. The jetliner scraped the peak of Bashún Hill, exploded, and slid down into a ravine; there were no survivors. Two minutes after the plane signal was lost from the radar screen, Cuenca air traffic control declared an emergency. The following day, search aircraft and rescue teams arrived the plane's last known position. Because of the remoteness and the difficulty of access to the crash site, it took rescue personnel several hours to reach the site itself.
Investigation
After initial fears of a possible sabotage were advanced by the civil aviation authorities after a radio station reported witnesses to a mid-air explosion. During the investigation, this was discarded due to lack of evidence. The civil authorities of aviation initiated an investigation, with cooperation of Boeing, Pratt & Whitney and the United States National Transportation Safety Board. The investigation results were presented several months later and concluded that pilot error was a direct cause the crash. Several factors were identified: training of the pilots was not properly delivered by TAME for the Boeing 737-2V2 Advanced, the crew was not fully familiar with the controls of the aircraft, and the crew was distracted while trying to locate the runway in heavy fog, as a consequence, the plane went below the minimum safe altitude in a mountainous region with the flight crew ignoring the voice commands of the proximity radar until seconds before impact.
