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 ( the first officer 's ) 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 ( due to the clear weather relaxing them ) , 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
Avianca Flight 203
Avianca Flight 203
Intercontinental de Aviación Flight 256