American Airlines Flight 965
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Summary | |
---|---|
Date | December 20, 1995 |
Type | Controlled flight into terrain |
Site | Buga, Colombia |
Fatalities | 159 |
Injuries | 4 |
Aircraft | |
Aircraft type | Boeing 757-223 |
Operator | American Airlines |
Tail number | N651AA |
Passengers | 155 |
Crew | 8 |
Survivors | 4 |
American Airlines Flight 965 was a scheduled flight from Miami International Airport in Miami, Florida to Alfonso Bonilla Aragón International Airport in Cali, Colombia. Flight 965 crashed into a mountain in Buga, Colombia on December 20, 1995.
On that day, the flight used N651AA, a Boeing 757 (previously flown by Eastern Air Lines, which sold its South American routes to American in 1990), carrying 155 passengers and 8 crew members. At 9:40 PM, just five minutes before its scheduled arrival, the plane went down in the Andes, in the first fatal 757 incident in U.S. history, and at the time, the worst U.S. air disaster since the downing of Pan Am Flight 103 seven years before. Only four passengers and a dog survived the crash.
Due to an attack by anti-government guerrillas in 1992, Cali's air traffic controllers had no radar to monitor the 757 as the pilots flew the approach using the area's radio instruments and airport's instrument approach system. Cali's approach uses several radio beacons to guide pilots around the mountains and canyons that surround the city. The airplane's flight management system already had these beacons programmed in, and should have, in theory, told the pilots exactly where to turn, climb, and descend, all the way from Miami to the terminal in Cali.
Since the weather was fair, Cali's controllers asked the pilots if they wanted to fly a straight-in approach to runway 19, rather than coming around to runway 01. The pilots agreed, hoping to make up some time – their departure from Miami had been delayed by two hours. Misinterpreting the word "direct", they cleared the approach waypoints from their navigation computer. When the controller asked the pilots to check back in over Tuluá, north of Cali it was no longer programmed into the computer, and so they had to pull out their maps to find it. In the meantime, they extended the aircraft's spoilers to slow it down and expedite its descent.
By the time they found Tuluá's coordinates, they had already passed over it. In response to this, they attempted to program the navigation computer for the next approach waypoint, Rozo. However, the Rozo NDB was identified as R on their charts. Colombia had duplicated the identifier for the Romeo NDB near Bogotá, and the computer's list of stored waypoints did not include the Rozo NDB as "R", but only under its full name "ROZO". In cases where a country allowed duplicate identifiers it often listed them with the largest city first. By picking the first "R" from the list, the captain caused the autopilot to start flying a course to Bogotá, resulting in the airplane turning east in a wide semicircle. By the time the error was detected, the aircraft was in a valley running roughly north-south parallel to the one they should have been in. The pilots had put the aircraft on a collision course with a 3,000-meter mountain.[1]
Nine seconds before the plane hit the mountain, 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, but the spoilers reduced the climb rate and the aircraft hit the mountain near its peak. Research has shown that the aircraft would probably have cleared the terrain if the crew had immediately retracted the spoilers when they were notified by the GPWS.
American Airlines settled numerous lawsuits brought against it by the families of the victims of the accident. American Airlines filed a "third party complaint" lawsuit for contribution against Jeppesen and Honeywell, who made the navigation computer database and failed to include the coordinates of Rozo under the identifier "R"; the case went to trial in United States District Court for the Southern District of Florida in Miami. At the trial American admitted that it bore some legal responsibility for the accident. Honeywell and Jeppesen each contended that they had no legal responsibility for the accident. In June 2000, the jury found that Jeppesen was 17% at fault for the crash, Honeywell was 8% at fault, and American Airlines was 75% at fault.
Cali's old approach system and lack of radar have both been blamed. Many pilots have also blamed the lack of a flight engineer in modern cockpits, which places a greater workload on the two pilots in front. Many blamed the pilots for not studying the Cali approach before attempting to land there. Boeing has been blamed for not equipping its spoilers to automatically retract when the aircraft accelerates.
The flight route designation of the Miami to Cali route is now Flight 921. Rozo NDB "R" has been replaced by Palma NDB "PL".
[edit] Crash investigation and final report
The crash was investigated by Aeronautica Civil (civil aviation authority) of the Republic of Colombia,[2] with assistance from the U.S. National Transportation Safety Board (U.S. NTSB) as well as other parties, including the U.S. Federal Aviation Administration, Allied Pilots Association, American Airlines, Boeing Commercial Airplane Group and Rolls Royce Engines.
The Aeronautica Civil prepared a final report of its investigation in September 1996, which was released through the U.S. NTSB.[3]
In its report, the Aeronautica Civil determined the following probable causes of the accident:
- The flightcrew's failure to adequately plan and execute the approach to runway 19 at SKCL and their inadequate use of automation.
- Failure of the flightcrew to discontinue the approach into Cali, despite numerous cues alerting them of the inadvisability of continuing the approach.
- The lack of situational awareness of the flightcrew regarding vertical navigation, proximity to terrain, and the relative location of critical radio aids.
- Failure of the flightcrew to revert to basic radio navigation at the time when the FMS-assisted navigation became confusing and demanded an excessive workload in a critical phase of the flight.
In addition, the Aeronautica Civil determined there were the following contributing factors to the accident:
- The flightcrew's ongoing efforts to expedite their approach and landing in order to avoid potential delays.
- The flightcrew's execution of the GPWS escape maneuver while the speedbrakes remained deployed.
- FMS logic that dropped all intermediate fixes from the display(s) in the event of execution of a direct routing.
- FMS-generated navigational information that used a different naming convention from that published in navigational charts.
The Aeronautica Civil's report also included a variety of safety-related recommendations to the following parties (number of individual recommendations in parentheses)[2]:
[edit] See also
[edit] References
- ^ AOPA "Lessons from Cali" Article
- ^ a b Aeronautica Civil's Final Report
- ^ NTSB Report Summary (Note: passenger number on NTSB summary is 156, vs. 155 on final report)