One of the crew members, his voice reflecting growing concern, sends an urgent message to air traffic controllers at the Colombian airport.
"Miss, Lima-Mike-India 2933 it's in failure, uh, total... electrical and fuel [failure]."
Less than 30 seconds later, the crew was back in touch with a frantic call for directions to line up for the approach to the runway.
Pilot: Lima-Mike India... vectors! Vectors, miss! Vectors to the runway!
But the jet's radar signal was lost, leaving the air traffic controller blindly directing the pilot to safety.
Controller: Direction... turn left 010 and proceed to the Rio Negro localizer 1 mile ahead of the border. At the moment, you're located, correct, I'm confirming going left with direction 350.
Pilot: Left 350.
Controller: Yes, correct. You're at zero-point-one miles to the Rio Negro border. I don't have your altitude, Lima-Mike-India.
Pilot: 9,000 feet, miss. Vectors, vectors!
Controller: You're 8.2 miles to the runway. What's your altitude now?
Lack of fuel to blame?
The Colombian Civil Aviation Authority could not confirm the authenticity of the recording, which offers new details of the final moments of the Monday crash of the aircraft that killed 71 people.
It was played Wednesday on Colombian media; it's not known how much more was recorded. Two sources familiar with the investigation who heard the recording confirmed the crew's reported electric failure and lack of fuel.
The British Aerospace Avro RJ85 was carrying 77 people, including members of Brazilian soccer squad Chapecoense, bound for the Copa Sudamericana finals in Colombia. Three players, two crew members and one journalist survived.
The audio bolsters investigators' suspicions the jet had depleted its fuel
during its charter flight from Santa Cruz, Bolivia.
The conversation appears to line up with an eyewitness account of a pilot in the sky who claims to have watched the jet rapidly descend. Colombian media published the account, but aviation officials could not confirm its authenticity.
Eyewitness account surfaces
Avianca Airlines co-pilot Juan Sebastian Upegui said he was listening to the radio as he watched the jet pass to the side of his plane "going downwards, fast as s---t," according to the recording.
"We even saw the plane lights as it was going down," he said, recalling the crew member's cries: "'We now have total electrical failure! We now have total electrical failure! Coordinates to proceed to the runway!'"
In the audio, Upedgui recalled that the LaMia crew did not declare a specific emergency regarding low fuel, a fact his co-pilot remarked upon.
"'They have fuel problems and are not declaring an emergency?'"