Flight segment

Time

(EST)

Event

1

20:18:00

Aircraft took off JFK airport. First officer Stephan Loew runs the aircraft

2

20:33-20:47

Radio blackout

3

21:10

Captain Urs Zimmermann and first officer Stephan Loew detected an odor in the cockpit and determined it to be smoke from the air conditioning system, a situation easily remedied by closing the air conditioning vent, which a flight attendant did on Zimmermann's request

4

21:14

Odor returned and smoke became visible. The crew called ATC Moncton indicating an urgent, but not an emergency, problem, and requested a diversion to Boston's Logan Airport, which was 300 nm (560km) away. ATC Moncton offered a vector to the closer Halifax Airport in Enfield, Nova Scotia, 66nm (104km) away, which Loew accepted.

5

21:14-21:34

The crew put on oxygen masks and the aircraft began to descent. Zimmermann put Loew in charge of the descent, while he ran through the Swissair checklists for smoke in the cockpit, a process that become later a source of controversy.

6

21:18

ATC Moncton handed over traffic control of Swissair 111 to ATC Halifax.

7

21:19

The plane was 30 nm (56km) away from Halifax Airport, but Loew requested more time to descend the plane from its altitude of 6,400m.

8

21:20

Loew informed ATC Halifax that he needed to dump fuel. ATC Halifax said later it was a surprise, because the request came so late. Dumping fuel was a fairly standard procedure early on in nearly any "heavy" aircraft urgent landing scenario. Subsequently, ATC Halifax diverted aircraft toward St. Margaret's Bay, where they could more safely dump fuel, but still be only around 30 nm (56km) from Halifax.

9

21:24:28

In accordance with the Swissair "In case of smoke of unknown origin" checklist, the crew shut off the power supply in the cabin. This caused the re-circulating fans to shut off. This caused a vacuum, which induced the fire to spread back into the cockpit. This also caused the autopilot to shut down. Loew informed ATC Halifax that "we now must fly manually."

10

21:24:45

Loew informed ATC Halifax that "Swissair 111 is declaring emergency"

11

21:24:46

Loew repeated the emergency declaration one second later, and over the next 10 seconds stated that they had descended to "between 12,000 and 5,000 feet" and once more declared an emergency.

12

21:25:40

The flight data recorder stopped recording, followed one second later by the cockpit voice recorder.

13

21:25:50-21:26:04

The doomed plane briefly showed up again on radar screens. Its last recorded altitude was 9,700 feet. Shortly after the first emergency declaration, the captain could be heard leaving his seat to fight the fire, which was now spreading to the rear of the cockpit.