The aircraft appears to have suffered an electrical failure, cutting off the flight-data recorder six minutes before the crash.
The last words on the transcript are from the air-traffic controller: "You're cleared to start the fuel dump", by which time the plane was plunging out of control.
The following are excerpts from a complete transcript of the final conversations on 2 September involving Swissair flight 111 and air-traffic control centres in Moncton, New Brunswick, and Halifax.
9:58.15 EDT [1:58.15 BST], Swissair 111: Moncton Centre, Swissair one- one-one heavy [a term for a wide-bodied plane] good, uh, evening, level three-three-zero [flying level at 33,000 feet].
9:58.20, Moncton controller: Swissair one-eleven heavy, Moncton Centre, good evening. Reports of occasional light turbulence at all levels.
10:14.18, Swissair 111: Swissair one-eleven heavy is declaring Pan Pan Pan [term for an urgent message, short of a distress call]. We have, uh, smoke in the cockpit. Uh, request immediate return, uh, to a convenient place, I guess, uh, Boston.
10:14.33, Moncton controller: Swissair one-eleven, roger ... turn right proceed ... uh ... you say to Boston you want to go?
10:14.33, Swissair 111: I guess Boston . . . we need first the weather, so, uh, we start a right turn here. Swissair one-one-one heavy.
10:14.45, Moncton controller: Swissair one-eleven, roger, and a descent to flight level three-one-zero [31,000 feet]. Is that OK?
10:14.50, Swissair 111: Three-one-zero. [Unintelligible words obscured by a noise, possibly associated with donning oxygen masks.] Three-one- zero . . . one-one heavy.
10:15.08, Moncton controller: Uh, would you prefer to go into Halifax?
10:15.11, Swissair 111: Uh, stand by.
10:15.38, Swissair 111: Affirmative for Swissair one-eleven heavy. We prefer Halifax from our position.
10:15.43, Moncton controller: Swissair one-eleven, roger. Proceed direct to Halifax. Descend now to flight level two-nine-zero [29,000 feet].
10:15.58, British Airways 214: And, uh, Swissair one-eleven heavy, from Speedbird [British Airways flight] two-one-four, I can give you the Halifax weather if you like.
10:16.04, Swissair 111: Swissair one-eleven heavy, we have the, uh, the oxygen mask on. Go ahead with the weather.
10:19.14, Halifax controller: OK, can I vector [direct] you, uh, to set up for runway zero-six at Halifax?
10:19.19, Swissair 111: Ah, say again latest wind, please.
10:19.22, Halifax controller: OK, active runway Halifax zero-six. Should I start you on a vector for six?
10:19.26, Swissair 111: Yes, uh, vector for six will be fine. Swissair one-eleven heavy.
10:19.39, Halifax controller: OK, it's a back-course approach for runway zero-six [the runway has a "localiser" radio signal that shows the runway's location, but the system does not automatically show the pilot the precise descent angle]. The localiser frequency one-zero-niner- decimal-niner. You've got 30 miles to fly to the threshold.
10:19.53, Swissair 111: Uh, we need more than thirty miles.
10:21.23, Halifax controller:
Swissair one-eleven, when you have time, could I have the number of souls on board and your fuel onboard please, for emergency services.
10:21.30, Swissair 111: Roger. At the time, uh, fuel on board is, uh, two-three-zero tons. We must, uh, dump some fuel. May we do that in this area during descent?
[Note: Two three zero tons represents the current gross weight of the aircraft, not the amount of fuel on board.]
10:22.04, Halifax controller: Swissair one-eleven, uh roger, uh turn to the ah, left, heading of, ah, two-zero-zero degrees and advise time when you are ready to dump.
It will be about 10 miles before you are off the coast. You are still within about 25 miles of the airport.
10:22.20, Swissair 111: Roger, we are turning left and, ah, in that case we're descending at the time only to ten thousand feet to dump the fuel.
10:22.29, Halifax controller: OK, maintain one-zero-thousand.
I'll advise you when you are over the water and it will be very shortly.
10:22.34, Swissair 111: Roger.
10:22.36, Swissair 111: [Conversation between the pilots, inadvertently broadcast on the air] Du bisch emergency checklist fur air-conditioning smoke? [Translation: You are in the emergency checklist for air- conditioning smoke?]
10:24.28, Swissair 111: [Background phone]. Ah, Swissair one-eleven.
At the time we must fly, ah, manually. Are we cleared to fly between, ah, ten thou ... eleven thousand and niner thousand feet? [Sound of audible signal when the autopilot is switched off.]
10:24.45, Swissair 111: Swissair one-eleven heavy is declaring emergency.
10:24.56, Swissair 111: Eleven heavy, we starting dump now, we have to land immediate.
10:25.00, Halifax controller: Swissair one-eleven, just a couple of miles, I'll be right with you.
10:25.19, Halifax controller: Swissair one-eleven, you are cleared to, ah, commence your fuel dump on that track [while maintaining your present direction] and advise me, ah, when the dump is complete.
10:25.43, Halifax controller: Swissair one-eleven, check you're cleared to start the fuel dump.
No further communications were heard from the Swissair plane. It disappeared from radar screens about six minutes later.
t The first law suit arising from the crash was brought in New York yesterday by Jake La Motta, the former middle-weight boxer played by Robert De Niro in the film Raging Bull.
His son, Joseph, was killed in the crash. Defendants in the suit include Swissair and Delta Airlines, McDonnell Douglas, which manufactured the MD-11 plane, and Boeing, which now owns McDonnell Douglas.
The law suit alleges the crash was caused by "electrical, mechanical and/or structural failure."Reuse content