American 965

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smhusain_1
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American 965

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Controlled Flight into Terrain--American Airlines 965
Investigated by Aeronautica Civil Colombia, Santafe de Bogota,
NTSB Washington D.C.
Type: B757-223, Registration: N651AA

History of Flight
At 2142 EST, on Dec. 20, 1995, American Airlines Flight 965 on a scheduled passenger flight from Miami (MIA) Florida, USA to Alfonso Bonilla Aragon International Airport (SKCL) in Cali, Colombia, and 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 (CLO). The aircraft impacted terrain at about 8900 feet ASL, near the summit of El Deluvio and approximately 10 miles east of Airway W3. Of the 163 souls on board including 8 crew members, 4 passengers survived the accident.

Airfield information
Alfonso Bonilla Aragon Airport (SKCL) in Cali in the Cordillera Occidental is located in a 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 approximately 7.5 miles north of CLO, at an elevation of 3162 feet ASL. The approach is flown in the valley, and then via circling for Runway 01 after reporting over Rozo via Tulua.
Runway 01 had instrument landing system (ILS) CAT 1 and VOR/DME approaches available. Precision Approach Path indicator (PAPI) gives visual glide path lighting and was available.
Runway 19 had a VOR/DME approach and included the PAPI.

Two standard arrivals (STARs) were available, one from the north of the airport (ROZO 1) and one from the east (MANGA 1). There were 12 published departures available. Radio navigational facilities included the ILS (IPAS), the Cali VOR (CLO), Rozo NDB (R), the middle marker (AS), and the Cali NDB (CLO). The Tulua VOR (ULQ) was approximately 33 nautical miles north of the airfield (43 DME from CLO), and was the initial point depicted on the ROZO 1 arrival. The airport was served by Cali Approach. No approach control radar was available. The airport control tower operated 24 hours a day for arriving and departing traffic to runways 01 and 19.

Scheduled departure was 1640 but actual departure time was 1835. Estimated enroute time (EET) was 3 hours and 12 minutes. Cruise at FL370 (thirty seven thousand feet above mean sea level). Route of flight from Miami is through the Cuban, Jamaican and into the Columbian airspace, where the flight was recleared by Barranquilla Centre to proceed from KILER intersection direct to BUTAL intersection. The flight then passed abeam Cartegena (CTG). Bogota Centre subsequently cleared the flight to fly direct from BUTAL to the Tulua VOR (ULQ).

Cali weather at 2111: clear, visibility greater than 10 kilometers with scattered clouds

Crew
Captain, 57. Total Time is 13,000 hours, 2260 hours on type B757/767. Flew 13 times into Cali before the accident flight of which the last two were on Dec 9 and 14, 1995. Described by colleagues as a non-smoker, in exemplary health and respected for his professional skills.

First Officer, 39. Total Time is 5800 hours, 2286 hours on type B757/767. With AA for 9 years, on first trip to Cali. Described by colleagues as professionally competent and appropriately assertive as a flight crew member.

AA965 (2126:16)-- requested descent clearance.

Flight initially cleared down to FL240 and then to FL 200 (Flight level two zero-zero means twenty thousand feet above mean sea level)

2134:04-AA965 instructed by Bogota Centre to contact Cali Approach Control

AA965 (2134:40) -- “Cali approach, American niner six five” (captain making the radio transmissions)

Cali Approach—“American niner six five, good evening, go ahead”

AA965-“ah Buenos noches senor, American niner six five, leaving two three zero descending to two zero-zero, go ahead sir.”

Cali Approach-“the uh, distance DME from Cali?”

AA965—“the DME is six three.” Six three--refers to distance from the Cali VOR* in nautical miles
*Navigational aid


Cali Approach-“roger, is cleared to Cali VOR, uh, descend and maintain one, five thousand feet, altimeter three zero-zero two, no delay expect for approach, report uh, Tulua VOR.” (Altimeter refers to sea level pressure in inches of mercury as 30.02 inches of Hg)

AA965—“OK, understood, cleared direct to Cali VOR, uh, report Tulua and altitude one five, that’s fifteen thousand, three zero-zero two, is that all correct sir?

Cali Approach--“affirmative.”

AA965 (2135:27)—“Thank you.”

Captain to First Officer (2135:28)—“put direct Cali for you in there.”

Captain punches direct to Cali on FMS (Flight Management Computer), so Tulua and Rozo way points erased on FMS italics mine

The accident aircraft incorporated a flight management system (FMS) that included a 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, through electronically-generated cathode ray tube (CRT) displays. The pilot input into the FMS could be performed either through a key board and associated cathode ray tube (CRT), known as a control display unit (CDU), or through a more limited FMS input via controls on the glareshield panel.

Cali Approach (2136:01)—“sir, the wind is calm, are you able to [execute the] approach [to] runway one niner.”

AA965—“uh yes sir, we’ll need lower altitude right away though.”

Cali Approach—“roger, American niner six five is cleared to VOR DME approach runway one niner,

Rozo number one arrival, report Tulua VOR.”

AA965—“cleared the VOR DME to one nine, Rozo one arrival, will report the VOR, thank you sir.”

Captain thinks he is cleared direct to Cali but controller wants him to report Taluhaitalics mine

Cali Approach—“report uh, Tulua VOR.”

AA965—“report Tulua.”

AA965 (2137:29)—“can American airlines uh, nine six five go direct to Rozo and then do the Rozo arrival sir”?

Cali Approach—“affirmative, take the Rozo one and runway one niner, the wind is calm.”

AA965—“alright Rozo, the Rozo one to one nine, thank you, American nine six five.”

Cali Approach—“report Tulua and e’eh, twenty one miles ah, five thousand feet.”

AA965—“OK, report Tulua twenty one miles and five thousand feet, American nine uh, six five.”

At 2137, after passing ULQ (Tulua VOR position Flight Data Recorder based) during its descent, the aircraft to turn to the left of the cleared course and flew on an easterly heading for approximately one minute. Then the aircraft turned to the right, while still in the descent. At 2139:25, Morse code for the letters ‘VC’ was recorded by navigation radio onto the aircraft’s cockpit voice recorder. At

2139:29, Morse code similar to the letters ‘ULQ’ was recorded.

AA965 (2140:01)—“and American uh, 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?”

Cali Approach—“you can [unintelligible word] landed, runway one niner, you can use runway one niner, what is [your] altitude and [the] DME from Cali?”

AA965—“Ok, we’re thirty seven DME* at ten thousand.”
*37 DME north of Cali VOR (CLO) places the aircraft 6 miles south of ULQ and 28 miles north of the approach end of runway 19 at Cali (SKCL).

Cali Approach (2140:25)—“roger, report uh five thousand and uh, final to runway one niner.”

The CVR recorded the flight crew’s conversations as well as radio transmissions.

Captain to First Officer (2140:40) -- “it’s that [expletive] Tulua I’m not getting for some reason, see

I can’t get, OK now, no, Tulua [expletive] up.”

Captain to First Officer (2140:49)—“but I can put in the box if you want it.”

First Officer to Captain—“I don’t want Tulua, let’s just go to the extended centerline of uh . . .”

Captain to First Officer—“which is Rozo.”

Captain to First Officer (2140:56)—“why don’t you just go direct to Rozo then, alright?”

First Officer to Captain—“Ok, let’s…

Captain to First Officer—“I’m goin’ to put that over you.”

First Officer to Captain—“… get some altimeters, we’re out of uh, ten now.”

At 2141:02, Cali Approach requested the flight’s altitude

AA965—“nine six five, nine thousand feet.”

Cali Approach (2141:10)—“roger, distance now?”

The flight crew did not respond to the controller.

At 2141:15, the cockpit voice recorder (CVR) recorded from the cockpit area microphone the mechanical voice and sounds of the aircraft’s ground proximity warning system (GPWS), “terrain, terrain, whoop, whoop.”

Captain--“Oh (expletive).”

A sound similar to autopilot disconnect warning began.

Captain-- “…pull up baby.”

The mechanical voice and sound continued, “… pull up, whoop, whoop, pull up.”

The FDR showed that the flight crew added full power and raised the nose of the aircraft; the spoilers (speedbrakes) that had been extended during the descent were not retracted. The aircraft entered into the regime of stick shaker stall warning, nose up attitude was lowered slightly, the aircraft came out of stick shaker warning, nose up attitude then increased and stick shaker was re-entered. The CVR ended at 2148:28.

The wreckage path and FDR data evidenced that the aircraft was on a magnetic heading of 223 degrees, nose up, and wings approximately level, as it struck trees at about 8900 feet above sea level on the east side of El Deluvio. The aircraft continue over the ridge near the summit and impacted and burned on the west side of the mountain, at North 03 degrees, 50 minutes, 45.2 seconds, latitude and West 76 degrees, 06 minutes and 17.1 seconds of longitude.

Findings

American Airlines provided training in flying in South America that provide flightcrews with adequate information regarding the hazards unique to operating there
The AA965 flightcrew accepted the offer by the Cali Approach controller to land on runway 19 at SKCL.
The flightcrew expressed concern about possible delays and accepted an offer to expedite their approach into Cali
The flightcrew had insufficient time to prepare for the approach to runway 19 before beginning the approach
The flightcrew failed to discontinue the approach despite their confusion regarding elements of the approach and numerous cues indicating the inadvisability of continuing the approach
Numerous important differences existed between the display of identical navigation data on approach charts and on FMS-generated displays despite the fact that the same supplier provided AA with navigational data.
The AA965 was not informed or aware of the fact that the “R” identifier that appeared on the approach (Rozo) did not correspond to the “R” identifier (Romeo) that they entered and executed a FMS command.

FMC offered a list of ‘Rs,” so captain selected first ‘R’ on top of list. This is not cross checked with First Officer, provisional track showing left turn and back. First ‘R’ stands for Bogota, 132 miles behind them at 7 o’clock position. Aircraft starts going there.
italics mine

One of the AA965 pilots selected a direct course to the Romeo NDB believing that it was the Rozo NDB, and upon executing the selection in the FMS permitted a turn of the aircraft towards Romeo, without having verified that it was the correct selection and without having first obtained approval of the other pilot, contrary to AA’s procedures
The incorrect FMS entry led to the aircraft departing the inbound course to Cali and turning it towards the city of Bogota. The subsequent turn to intercept the extended centerline of runway 19 led to the turn towards high terrain
The descent was continuous from FL230 until the crash
Neither pilot recognized that the speedbrakes were extended during the GPWS escape maneuver, due to lack of clue available to alert them about the extended condition
The Cali approach controller followed applicable ICAO and Colombian air traffic control rules and did not contribute to the cause of the accident

Probable Causes
Aeronautica Civil determines that the probable causes of this accident were:

The flightcrew 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.

Contributing Factors

Contributing to the cause of the accident was:

The flight crew’s ongoing efforts to expedite their approach and landing in order to avoid potential delays.
The flight crew’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