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AA965 Cali Accident Report
Near Buga, Colombia, Dec 20, 1995
Prepared for the WWW by Peter Ladkin Universität Bielefeld Germany
Prepared November 6, 1996
[Preparer's Note: Footnote markers are written in square brackets, e.g., [22], and footnotes appear denoted by the same figures in brackets at the bottom of the same page, separated from the page contents by a dashed line. Typographical errors have been retained in the original as far as possible, except for occasional double full stops at the ends of some paragraphs. PBL]
AERONAUTICA CIVIL of THE REPUBLIC OF COLOMBIA
SANTAFE DE BOGOTA, D.C. - COLOMBIA
AIRCRAFT ACCIDENT REPORT
CONTROLLED FLIGHT INTO TERRAIN AMERICAN AIRLINES FLIGHT 965 BOEING 757-223, N651AA NEAR CALI, COLOMBIA DECEMBER 20, 1995
CONTENTS
AIRCRAFT ACCIDENT REPORT
AERONAUTICA CIVIL OF THE REPUBLIC OF COLOMBIA
SANTAFE DE BOGOTA, D.C. - COLOMBIA
CONTROLLED FLIGHT INTO TERRAIN
AMERICAN AIRLINES FLIGHT 965, BOEING 757-223, N651AA
NEAR CALI, COLOMBIA, DECEMBER 20, 1995
1. FACTUAL INFORMATION
1.1 History of Flight
At 2142 eastern standard time (est) [l], on December 20, 1995, American Airlines Flight 965 (AA965), a Boeing 757-223, N651AA, on a regularly scheduled passenger flight from Miami International Airport (MIA), Florida, U.S.A., to Alfonso Bonilla Aragon International Airport (SKCL), in Cali, Colombia, operating under instrument flight rules (IFR), crashed into mountainous terrain during a descent from cruise altitude in visual meteorological conditions (VMC). The accident site was near the town of Buga, 33 miles northeast of the Cali VOR [2] (CLO). The airplane impacted at about 8,900 feet mean sea level (msl), near the summit of El Deluvio and approximately 10 miles east of Airway W3. Of the 155 passengers, 2 flightcrew members, and 6 cabincrew members on board, 4 passengers survived the accident.
On the previous flight under a different crew, the airplane arrived at MIA from Guayaquil, Equador, at 1438, on December 20, 1996. The Guayaquil to MIA flightcrew reported that there were no significant maintenance or operations-related discrepancies on the airplane. The captain and first officer of AA965 (MIA to SKCL) arrived at the airline's MIA operations office about 1 hour before the proposed departure time of 1640. The operations base manager later stated that
[1] All times herein are expressed in est, based on the 24-hour clock, unless otherwise indicated. The Colombian and MIA local time was the same (est).
[2] Very high frequency (VHF) omni-directional radio range.
both the captain and first officer were in his office about 40 minutes before the required check-in time, and appeared to be in good spirits.
According to the AA flight dispatcher at MIA, AA965 was delayed about 34 minutes, waiting for the arrival of connecting passengers and baggage. The flight departed the gate at 1714, and then experienced another ground delay of 1 hour 21 minutes that the flight dispatcher stated was related to gate congestion due to airport traffic. AA965 departed MIA at 1835, with an estimated time enroute to Cali of 3 hour 12 minutes.
AA965 was cleared to climb to flight level (FL) 370 [3]. The route of flight was from MIA through Cuban airspace, then through Jamaican airspace, and into Colombian airspace, where the flight was recleared by Barranquilla Air Traffic Control Center (Barranquilla Center) to proceed from KILER Intersection direct to BUTAL Intersection. The flight then passed abeam Cartegena (CTG). Bogota Center subsequently cleared the flight to fly direct from BUTAL to the Tulua VOR (ULQ)
At 2103, AA965 estimated to Bogota Center that they would cross BUTAL at 2107. As AA passed BUTAL, Bogota Center again cleared the flight from its present position to ULQ, and told the flight to report when they were ready to descend. At 2110, AA965 communicated via ACARS [4] with AA's System Operations Control (SOC) center, asking for weather information at Cali. At 2111, Cali weather was reported as clear, visibility greater than 10 kilometers, and scattered clouds. At 2126:16, AA965 requested descent clearance. The flight was initially cleared to FL 240 and then to FL 200. At 2134:04, the flight was instructed to contact Cali Approach Control (Approach).
AA965 contacted Approach at 2134:40. The captain, making the radio transmissions [5] said, "Cali approach, American nine six five." The approach controller replied, "American niner six five, good evening. go ahead." The captain stated, "ah, buenos noches senor, American nine six five leaving two three zero, descending to two zero zero. go ahead sir." The controller asked, "the uh, distance DME [6] from Cali?" The captain replied, "the DME is six three." The controller
[3] 37,000 feet. Flight levels are expressed in hundreds of feet above msl.
[4]Aircraft Communications Addressing and Reporting System.
[5] Based on the air traffic control (ATC) and cockpit voice recordings (CVR), the captain made the radio communications and the first officer was at the controls of the airplane.
[6]Distance measuring equipment, providing a display in nautical miles.
thirty eight miles north of Cali, and you want us to go Tulua and then do the Rozo uh, to uh, the runway, right to runway one nine?" The controller answered, "...you can [unintelligible word] landed, runway one niner, you can use runway one niner. what is (you) altitude and (the) DME from Cali?" The flight responded, "OK, we're thirty seven DME [10] at ten thousand feet." The controller stated at 2140:25, "roger. report (uh) five thousand and uh, final to one one, runway one niner."
The CVR recorded the flightcrew's conversations as well as radio transmissions. At 2140:40, the captain stated, "it's that [expletive] Tulua I'm not getting for some reason. see I can't get. OK now, no. Tulua's [expletive] up." At 2140:49 the captain said, "but I can put it in the box if you want it." The first officer replied, "I don't want Tulua. let's just go to the extended centerline of uh...." The captain stated, "which is Rozo." At 2140:56, the captain stated, "why don't you just go direct to Rozo then, alright?" The first officer replied, "OK, let's...The captain said, "I'm goin' to put that over you." The first officer replied, "...get some altimeters, we'er out of uh, ten now."
At 2141:02, Cali Approach requested the flight's altitude. The flight replied, "nine six five, nine thousand feet." The controller then asked at 2141: 10, "roger, distance now?" The flightcrew did not respond to the controller. At 2141:15, the CVR recorded from the cockpit area microphone the mechanical voice and sounds of the airplane's ground proximity warning system (GPWS), "terrain, terrain, whoop, whoop." The captain stated, "Oh [expletive]," and a sound similar to autopilot disconnect warning began. The captain said, "...pull up baby." The mechanical voice and sound continued, "...pull up, whoop, whoop, pull up." The FDR showed that the flightcrew added full power and raised the nose of the airplane, the spoilers (speedbrakes) that had been extended during the descent were not retracted. The airplane entered into the regime of stick shaker stall warning, nose up attitude was lowered slightly [11], the airplane came out of stick shaker warning, nose up attitude then increased and stick shaker was reentered. The CVR ended at 2141 :28.
The wreckage path and FDR data evidenced that the airplane was on a magnetic heading of 223 degrees, nose up, and wings approximately level, as it struck trees at about 8,900 feet msl on the east side of El Deluvio. The airplane
[10] 37 DME north of the Cali VOR (CLO) places the airplane 6 miles south of ULQ and 28 miles north of the approach end of runway 19 at SKCL.
[11] From FDR data.
continued over a ridge near the summit and impacted and burned on the west side of the mountain, at 3 degrees 50 minutes 45.2 seconds north latitude and 76 degrees 6 minutes 17. seconds west longitude. Approach unsuccessfully attempted to contact AA965 several times after the time of impact (see appendix D, two photographs of the accident site).
1.2 Injuries to Persons
Injuries Flightcrew Cabincrew Passengers Total
Fatal 2 6 151 159
Serious 0 0 4 4
Minor 0 0 0 0
None 0 0 0 0
Total 2 6 155 163
1.3 Damage to Airplane
The airplane was destroyed.
1.4 Other Damage
None. Impact was in tree-covered mountainous terrain.
1.5 Personnel Information
The captain and first officer were certified by the U.S. Federal Aviation Administration (FAA) to hold their respective positions in the Boeing 757 (B-757) and each possessed a current first class medical certificate. FAA records showed that neither had been involved in an accident, incident, or enforcement action.
1.5.1. Cockpit Crew
Pilot In Command First Officer
Age 57 39
Date of Birth 11/17/38 6/24/
Date of Hire with American Airlines 9/22/69 10/11/
First Class Medical Certificate Issued 12/7/
The captain's last medical examination was on December 7, 1995, when his Class I medical certificate was renewed. His certificate bore the following limitation: "Holder shall wear lenses that correct for distant vision and possess glasses that correct for near vision while exercising the privileges of this airman certificate."
The captain was described by his colleagues as a non-smoker, avid tennis player, in exemplary health, and respected for his professional skills, including his skill in communicating with crewmembers and passengers. Company records contained numerous letters from passengers and company employees that reflected outstanding and courteous performance. The captain was married and had two adult children who lived outside of the home.
On the day of the accident, December 20, 1995, the captain arose around 0500. His wife began to prepare for a trip in her capacity as an AA flight attendant. She was later not sure whether the captain had returned to sleep after she departed their home at 0600. She estimated that he departed from home about 1200 for the drive to MIA.
The day prior to the accident, December 19, the captain awoke about 0700, and spent the day relaxing around the house and then playing tennis about l 1/2 hours with his wife. They returned home about 2130. From December 15 through 18, the captain and his wife visited his family in New Jersey, on what was described as an enjoyable Christmas visit that they took early because of the scheduled trips.
1.5.3 First Officer
The first officer began his flying eareer as a college undergraduate by enrolling in the U.S. Air Force Reserve Officer Training Corps. He began pilot training with the Air Force in 1979, flying a variety of aircraft, including trainers and F-4E fighters, through 1986. He served as an instructor in ground school, in flight simulators, and in airplanes, and in 1985 was awarded Air Force Instruetor of the Year.
The first officer beeame employed by AA on Oetober 11, 1986. Company reeords indicated that he had accumulated a total of 1,362 flight hours when hired. He began as a flight engineer on the B-727. Later duties included first
officer on the B-727, McDonnell Douglas (MD) 11, and B-757 and -767. He possessed type ratings in the MD 11 and B757/B767.
The first officer attended the AA 5-day qualification and recurrence course and satisfactorily completed the required annual simulator check on November 27, 1995. As part of that sequence, annual recurrent requirements also ineluded training regarding security, hazardous materials, CRM, and international operations. The first officer's annual line cheek was aeeomplished on August 31, 1995.
The first offieer's Class 1 medical certificate was renewed on June 21, 1995, with no limitations.
The first officer had never flown into Cali. However, he had flown to other destinations in South America as an internationally qualified B-757/767 first officer.
The first officer was described by his colleagues as professionally competent, and appropriately assertive as a flightcrew member. He was married and the father of three young children who lived at home.
On the day of the accident, the first officer arose about 0700, and had breakfast with his family. Around 0830, he worked with his wife to prepare for their children's home schooling aetivities. He later exercised. He visited with his father and family around midday and, around 1230, left for the airport at Orlando, Florida, for the flight to MIA.
On the day prior to the accident, December 19, the first officer arose about 0700, and had an 0830, appointment with an aviation medical examiner (AME) for a flight physical [13]. Afterwards, the first officer visited with his brother at his brother's place of business, and later the two had lunch. The first officer returned home at 1530, and played basketball with his children. The family had dinner about 1730, and at 1900, he, his wife, and children attended a basketball game where their son was playing. The family returned home about 2015, and at 2115 the first officer helped put the children to bed. He and his wife watched television briefly and retired about 2330.
[13] The AME later stated that the first officer was found in excellent health.
1.6.2 Flight Management System
The B-757 and -767 are flight management system (FMS)-equipped airplanes. The accident airplane incorporated an FMS that included an flight management computer (FMC), a worldwide navigation data base that contained radio frequencies, and latitude and longitude coordinates of relevant navigation aids as well as coordinates of airports capable of B-757 operations. The FMC data base also included B-757 performance data which, combined with pilot inputs, governed autothrottle and autopilot functions. The FMS monitored the system and engine status and displayed the information, as well as airplane attitude, flightpath, navigation, and other information, through electronically-generated cathode ray tube (CRT) displays [14].
Pilot input into the FMS could be performed either through a keyboard and associated cathode ray tube (CRT), known as a control display unit (CDU), or through more limited FMS input via controls on the glareshield (see section 1.16, regarding post-accident testing of FMS components).
1.7 Meteorological Information
The flight crew received the following AA terminal weather forecast for Cali in the flight dispatch records:
Cali at 0606 universal coordinated time (utc) [15]: Winds calm, visibility more than 10 kilometers, clouds scattered at 2,500 and 10,000 feet
Temporary change (Cali) from 0900 to 1300 utc: 8000 meters visibility, rain showers in the vicinity, clouds scattered at 2,000, broken at 8,500 feet
Temporary change (Cali) from 2000 through 0200 utc: Winds 360 degrees at 05 knots, rain showers in the vicinity, clouds scattered at 2,000 feet and broken at 8,000 feet
The flight departure paper recorded the weather at 1500 est as: Winds calm, visibility more than 10 kilometers, clouds scattered at 2,000 and 12,000 feet,
[14] On the instrument panel before each pilot
[15] Universal coordinate time. Est is 5 hours behind utc.
temperature 28 centigrade, dew point 18 degrees centigrade (C.), altimeter (QNH) 29.94 inches of mercury
The flight crew received an updated weather message via the ACARS. The weather was for 1700 est and was reported as:
(Cali): Winds 340 degrees at 06 knots, visibility more than 10 kilometers, rain showers in the vicinity, clouds scattered at 1,700 feet and broken at 10,000 feet, temperature 28 degrees C., dew point 18 degrees C., altimeter (QNH) 29.98 inches of mercury
Enroute, the flight crew requested the Cali weather via ACARS at 2050 est. The company replied at 2051, via ACARS, that there was "no current data."
At 2110 est, the flightcrew requested, again, the weather for Cali. At 2111, the flightcrew received via the uplink, the following weather information for 2000 local at Cali: Winds 160 degrees at 04 knots, visibility more than 10 kilometers, clouds scattered at 1,700 and 10,000 feet, temperature 23 degrees and dew point 18 degrees C., altimeter (QNH) 29.98 inches of mercury. This was the last request and uplink of weather recorded.
1.8 Aids to Navigation
There were no difficulties with aids to navigation.
1.9 Communications
There were no difficulties with communications equipment.
1.10 Aerodrome Information
Alfonso Bonilla Aragon Airport (SKCL) in Cali, is located in a long, narrow valley oriented north to south. Mountains extend up to 14,000 feet msl to the east and west of the valley. The airport is located approximately 7.5 miles north of CLO, at an elevation of 3,162 feet msl.
brake deployment. The data were recorded on a continuous 25 hour cycle in which the oldest data were erased and new data recorded.
The FDR was extensively damaged by impact forces. There was no evidence of fire damage to the recorder. The tape recording medium was undamaged. The FDR was brought to the U.S. National Transportation Safety Board's (NTSB's) laboratories in Washington, D.C., U.S.A., and read out.
1.11.2 Cockpit Voice Recorder
The airplane was equipped with a Fairchild model A-lOOa CVR, serial no. 59225. Examination in the NTSB CVR laboratory found exterior structural damage. The exterior case was cut away to access the tape medium. The tape did not sustain heat or impact damage. The recording was of good quality and a transcript was prepared of the entire 30:40 minute recording.
1.12 Wreckage and Impact Information
The airplane struck near the top of a mountain ridge about 35 miles northeast of Cali. The elevation of the top of the ridge was about 9,000 feet mean sea level. The airplane initially struck trees on the east side of the ridge, and the preponderance of the wreckage, which contained the occupants of the airplane and included both engines, came to rest on the west face of the ridge. There was no indication of in-flight fire or separation of parts before initial impact.
The initial impact area was marked by an area of broken trees, followed by a swath where the trees had been essentially flattened or uprooted. The area of uprooted trees began about 250 feet below the top of the ridge. The initial impact swath was oriented along a heading of about 220°. Wreckage that was found at the beginning of the wreckage path included thrust reverser parts, a fan cowling, an APU tail cone, flap jackscrews, an engine fire bottle, the FDR, and a small section of wing. The pattern of the broken trees indicated that the airplane initially struck at a high nose up attitude.
The main wreckage came to rest on the west side of the ridge, about 400 to 500 feet from the top. In addition to the engines, the largest portion of wreckage included the cockpit, a section of center fuselage about 35 feet long, the CVR, aviation electronics (avionics) boxes, a section of the aft fuselage, and a portion of the wing center section.
The wreckage evidence indicated that both flaps and landing gear were in the retracted position at the time of impact.
Both engines were examined on site. The left engine showed ingestion of soil and foliage as far aft as the inlet guide vanes to the intermediate compressor section. There was a substantial bending of fan blades in a counter-clockwise direction, with some bent clockwise.
The right engine was found slightly buried into the ground. The blade damage that was observable was similar to the damage observed on the left engine. Soil and foliage were found as far aft as the inlet to the intermediate compressor section. Neither engine showed evidence of fire damage.
Numerous cireuit cards and other parts that were onsidered likely to contain non-volatile memory were retrieved from the site, packed in static free material, and shipped to the United States for read out at the facilities of their manufacturers. With the exception of one circuit card from the Honeywell- manufaetured FMC, the material either did not contain non-volatile memory or was too severely damaged to permit data retrieval. Discussion of the data retrieval of the non-volatile memory from the FMC is located in section 1.16, Tests and Research.
1.13 Medical and Pathological Information
The body of the first officer was recovered on the first day after the accident. The body of the captain was retrieved from the crash site on the third day after the accident. The cause of death of each was determined to be blunt force trauma.
Specimens of liver, blood, and vitreous humor were obtained and analyzed by the Colombian Instituto Nacional de Medicina Legal. The samples from the body of the first officer were found to be negative for alcohol and drugs of abuse. The blood and liver samples from the captain were found to be positive for alcohol at 0.074 percent and 0.35 percent blood alcohol levels, respectively, and negative for drugs of abuse. Vitreous specimens were found to be negative for both pilots.
Portions of the liver and blood samples from the bodies of the flightcrew members were then flown to the United States to be further analyzed by
Company, in Englewood, Colorado; American Airlines in Fort Worth, Texas; and Boeing Commercial Airplane Group, in Seattle, Washington.
1.16.1 FMS Component Examinations
Portions of the FMS, including the FMC, that had been recovered from the wreckage, were examined at Honeywell Air Transport Systems.
After the components were cleaned for laboratory examination, it was found that the FMC contained a printed circuit card that had two non-volatile memory integrated circuits. Data recovered from the integrated circuits included a navigation data base, guidance buffer, built in test equipment (BITE) history file, operational program, and other reference information.
A load test of the FMC memory showed that the operational software and navigational data were current for the time of the accident. The BITE showed that there had been no recorded loss of function during the last 10 flights of the airplane.
The guidance buffer recorded that the FMC-planned route of flight at the point of power loss [16] was from the last passed waypoint, shown as KILER, direct to the next waypoint that had not yet been passed, shown as ULQ. The route beyond ULQ was shown as waypoint R, then CLO, then CLO03 [17], then the stored ILS runway 01 approach of CI01, then FI01, then RW01, then ROZO, then a hold [18] at ROZO.
When the FMC memory was first restored, a modification to the above route was displayed. The modified route was shown as ULQ, a ROUTE DISCONTINUITY message, then R, another ROUTE DISCONTINUITY message, then CLO, then CLO03, then CI01, then FI01, then RW01, then ROZO, then a hold at ROZO.
The FMC was put through a short term (power transient) initialization and the captain's and first officer's CDU displays were identical, as follows:
[16] Coinciding with the time of impact.
[17] CLO03 was found to be a point-bearing distance location.
[18] BITE provided non volatile memory of FMC activity for previous 10 flights of the accident airplane. Hold indicates routing to a preplanned holding pattern location.
MOD RTE 1 LEGS 1/
R 268/FL
THEN
IIIIII
--ROUTE DISCONTINUITY -
CLO 237/
161° 3NM
CLO03 207/
307° 2NM
CI01 189/
The CLO03 was not seen on a printed format of the route. When the (L4) line select key (LSK) for CLO03 was pressed, the scratch pad area (LSK L6) at the bottom of the screen was displayed:
CLO163.0/003.
Pushing the NEXT PAGE button showed:
MOD RTE LEGS 2/
013° 2NM
FI01 170/
013° 7NM
RW01 130/
013° 4NM
ROZO ---/3560A
HOLD AT
ROZO ---/
[19] The font size on the airspeeds and altitudes associated with CLO and CLO03 were smaller than the font sizes of comparable information for CI01. These differences indicate that the information for CI01 was inputted by the pilot whereas the information for CLO were generated by the FMS.
