Aeronautical Science - American Airlines

CASE STUDY #1: AMERICAN FLIGHT 965

by

Mario D. Ochoa

A Graduate Paper Submitted in Partial Fulfillment of the Requirements

for the Completion of MSA 608 Aviation and Aerospace Accident Investigation and Safety Systems and for the Degree of Master of Science in Aeronautics

Embry-Riddle Aeronautical University

Daytona Beach, Florida

2005

WHAT HAPPENED?

American Airlines (AA) Flight 965 out of Miami International crashed on December 20, 1995 in enroute to Cali, Columbia at approximately 9:42 PM Eastern Standard Time (EST). The airplane was a regularly scheduled flight out of Miami and a Boeing 757-233 with 163 passengers and crew on board (Cali Press Release -NTSB, 1995). The airplane crashed approximately 33 miles northeast of Cali on its approach to the airport, when it struck a mountain while descending for the approach. The crash occurred under visual meteorological conditions (VMC), at night, and with no significant weather. The accident occurred near the town of Buga, Columbia around the summit of El Deluvio at approximately 8,900 feet sea level.

WHY DID THE ACCIDENT HAPPEN?

AA Flight 965 accident happened due to a serious of "operational errors" leading to the catastrophe on the summit of El Deluvio. These errors, which individually were not causal, but interacted in a way that caused the accident when linked together, formed the "accident chain" (Bovier, 1997). In Dr. Diehl's Accident Model, it takes hundreds of hazards to lead to tens of incidents that eventually cause an accident (Hunt, 2005). In this accident, AA Flight 965 had many critical events, particular in the realm of crew resource management (CRM) and situational awareness (SA). These two realms are what affected the outcome of AA Flight 965 on its final minutes in flight and led to the "causation factor" of the accident.

The captain, non-flying crew member on the controls at the time of the accident, and the first officer, flying crew member, both had thousand of hours of flight time and thousands of hours in type aircraft. The last seven minutes of the flight (as reported by the handling investigation agency - Aeronautica Civil of the Government of Columbia) is the critical time that affected the outcome of AA Flight 965. The crew was originally going to fly the precision Instrument Landing System (ILS) approach into Cali, called Cali ILS Runway 01. The crew was offered the non-precision approach, Very high frequency approach Omnidirectional Range with Distance Measuring Equipment (VOR DME) Runway 19 by Air Traffic Control (ATC). This would allow the crew to basically fly a "straight-in" approach to Cali via the current route inbound. Executing this would allow the crew to save flight time and land sooner at the airport and not have to pass Cali to turn around and execute the Cali ILS Runway 01 approach Aeronautica Civil, 1996).

In reality, after the captain accepted the approach from ATC at Cali, the captain made a critical error in flight planning. The captain input the wrong waypoint into the Flight Management System (FMS) and started a series of errors immediately following for the next seven minutes - the last for AA Flight 965 (Bovier, 1997). By only confirming to the first officer that he had put the required waypoint into the FMS, the proper input was to be the "ROZO" non-directional beacon (NDB), the captain in reality made an input of "R" ("Romeo" waypoint) which led the automatic pilot with the Flight Management Computer (FMC) and all its components fly the aircraft to Bogota, Columbia. This course was due east of the desired course direction, heading 093 degrees, and should have been noticed by either crewmember if they had correct SA. By not recognizing the required input of "R-O-Z-O" into the FMS, the crew allowed the aircraft to turn in the wrong direction. Typing in on the letter "R" in the FMS led to this critical mistake (Aeronautica Civil, 1996).

The next few and systemic critical errors made by the crew, and not recognizing the chain of events, are what finally lead to AA Flight 965's dismayed crash. The crew did not communicate the approach charts, procedures, requirements, and/or crew brief on the newly assigned approach (VOR DME Runway 19). By not doing so, the crew achieved what aviation jargon calls "falling behind the aircraft" (Bovier, 1997). Their SA continued to diminish as time elapsed. No approach chart was pulled out to properly plan the new approach. The speedbrakes were added just prior to the descent, and an unknowledgeable sequence on proper FMS procedures (analysis of what the crew is telling the FMS to accomplish and what the crew desires out of the FMS) began to take place. This led to another human factor issue of lack of proper CRM (Garland, Wise, & Hopkins, 1999, Chapter 9).

The captain and the first officer did not know how the new route of flight should be flown. They both allowed the aircraft to be flown away from the proper course without any realization. The crew had a different perspective of where they were in relation to where they should be on their current position, attitude, and motion. The current SA and state of the aircraft could not be determined by neither crewmember, and this had a more definite and severe impact on the crew's ability to project the aircraft future projection. The difference in the "actual aircraft position" compared to the crew's current knowledge of its "present position," leads to critical errors of the flight. Setting the FMS directly to fly the plane to the "Romeo" beacon instead of "ROZO" beacon, the pilots became confused and failed to revert back to basic radio instrument navigational procedures (McCartney, 1996). The different in visual and mental pictures of aircraft position being displayed by the crew compared to the actual aircraft position is what eventually leads to the accident.

After the captain initially put in "R" into the FMS, and this steered the aircraft toward Bogota, the crew wanted to know about the Tulua VOR, which was erased from the flight plan due to the captain's action. The captain