The aircraft involved was a McDonnell Douglas DC-9-14 that had its maiden flight on 15 February 1966 and was initially registered as N8901E. The aircraft was initially powered by two Pratt & Whitney JT8D-7A engines, which developed 12,600 pounds of thrust. The plane was delivered to Eastern Air Lines on 26 April the same year. On 27 April 1970, the aircraft was leased to Delta Air Lines, and was returned to Eastern on 23 April 1971. On May 31, 1979, the aircraft was transferred to Texas International Airlines, which merged into Continental Airlines in 1982. On 31 October the same year, Continental Airlines named the aircraft City of Mexico City. Also in the latter the engines were upgraded, which were modified to the model JT8D-7B. Also, the configuration of the cabin of the aircraft was changed to 83 seats. The aircraft remained registered as N8901E. On 29 April 1993, the aircraft was transferred to Intercontinental de Aviación, where the aircraft was re-registered as HK-3839X. The aircraft was almost 29 years old and had 65,084 flight hours and 69,716 take-off and landing cycles at the time of the crash.
Passengers and crew
The captain of flight 256 was Andrés Patacón, and the first officer was Luis Ríos. In the cabin there were three flight attendants: Claudia Duarte, Dalia Mora and Zaida Tarazona. On board were 47 passengers, all of whom were Colombians.
Crash
The flight was scheduled to depart at 12:10 but was delayed due to a failure on the previous flight. The flight eventually departed at 18:45. The aircraft climbed to flight level 310 at 19:09. During the approach to Cartagena, the air traffic control center in Barranquilla cleared flight 256 to descend to FL 140 and report when passing FL 200 at 19:26. The aircraft passed through FL 200 at 19:33. The last radio contact occurred when the flight was cleared further down to. At 19:38, the crew of a Cessna Caravan aircraft, which operating flight 209 from Aerocorales, contacted the controllers. The crew reported that they had seen the lights of a rapidly descending aircraft, followed by an explosion on the ground. The plane impacted with the ground in a marshy lagoon near María La Baja, from Cartagena Airport. The plane exploded on impact and broke into three parts. 51 people were killed: 46 out of the 47 passengers and all 5 crew members. The sole survivor of the crash was a nine-year-old girl.
Investigation
Since the crew of the Cessna reported an explosion, first suspicions arose about a terrorist attack, similar to the bombing of Avianca Flight 203 in 1989. However, investigators determined that the plane exploded when it hit the ground, and no traces of explosives were found. The probable cause of the crash was a wrong setting of the altimeter. Altimeter number 1 indicated on impact. Altimeter number 2 worked normally, but its lights did not work, and therefore the crew could not compare their readings. Other contributing factors were the lack of radar observation in the area and the flight crew's loss of situational awareness, as well as the airline's insufficient training of crews in this situation. In addition, it was not possible to determine whether the ground proximity warning system functioned properly, or the crew was unable to respond to it in time.
