On 5 February, the crew returned to Montego Bay, where they received their assignment for flight 1851 from Milan, Italy, to Punta Cana, Dominican Republic, with a scheduled stopover in Santa Maria, Azores, Portugal.

On 7 February, after a flight of 10 hours and 40 minutes, the crew arrived in Genoa, Italy, having to divert from Milan Malpensa Airport due to poor weather.

[9] Departure was scheduled for 08:00 GMT, but because of fog, the aircraft was delayed in Genoa and was able to land at Orio al Serio Airport in Bergamo only at 07:20.

It is also worth noting that in terms of flight, the airport coordinates were given as 36756 North (latitude) and 025096 West (longitude), with the runway elevation being 0 feet.

[9] Flight 1851 had communication difficulties with air traffic controllers at high frequencies (HF), although it worked without failures on the ground.

At 12:46:33, the crew contacted the Santa Maria Air Traffic Control center and reported on the passage point 38°N 20°W / 38°N 20°W / 38; -20.

Radio communication with the land was conducted mainly by first officer Adcock, with the exception at 13:43:57 when flight engineer Gonzalez requested a weather report.

Due to the communication difficulties, the crew heard the message as "one octant two two zero zero," from which they falsely determined that there were no clouds below 2,000 feet.

[9] At 13:56:47, when flight 1851 was performing a descent to the airfield and passing 6,705 meters (21,998 ft), the controller dispatched: "Independent Air one eight five one roger you're cleared to three thousand feet on QNH one zero two seven and ah runway will be one niner."

At 14:06 at a speed of 250 knots (460 km/h; 290 mph), and at a height of 2,000 feet (610 m) the aircraft encountered heavy turbulence near Santo Espírito, with Daugherty saying at 14:07:52, "Can't keep this son of a bitch thing straight up and down."

[9] At 14:08:12, at an actual altitude of 1,795 feet (547 m) above sea level, the aircraft crashed into a wall by a road, skidded through trees with trunks about 30–40 centimeters (12–16 in) in diameter, and exploded.

[9] During that transmission, a trainee controller had also transmitted an incorrect QNH (barometric altimeter setting) that was 9 hPa too high.

The approach instructions were not fully heard since the pilot had re-keyed his microphone to acknowledge the new QNH, and likely did not hear the second repeat of the 3,000 ft safe altitude, declaring: "We're re-cleared to 2,000 feet..." (610 m).

The pilot in command cannot excuse his act by alleging the air traffic controller directed him to descend to an altitude of 2,000 feet and gave him an incorrect altimeter setting.

[13][14] The crash was featured in season 23, episode 2 of the Canadian documentary series Mayday, titled "Mixed Signals".