David Learmount/LONDON

Signs of "heating" damage have been detected in parts recovered from the cockpit of the Swissair Boeing MD-11 which crashed off Nova Scotia on 2 September, says chief accident investigator Vic Gerden. Gerden, of the Canadian Transportation Safety Board (CASB) would not be more precise or offer conclusions about the discovery.

The emergency had begun with a "Pan" emergency call from the crew declaring that there was smoke in the cockpit, and 16min later the aircraft crashed into the sea late at night. The crew had accepted the air traffic control offer of radar vectors to land at Halifax and was in descent from 33,000ft (10,000m), dumping fuel. Because the aircraft was too close to Halifax to descend for a straight-in approach to the proffered runway 06, the aircraft had turned over the sea to lose height and continue its fuel dump.

Now that the CASB has recovered the digital flight data recorder (FDR), it seems certain that there was a major interruption to the aircraft's electrical power supplies. The CASB says that the last 6min of the recording show nothing, and that tallies with the time before impact that the crew stopped communicating with ATC and the secondary radar returns from the aircraft's transponder to Moncton ATC Centre were lost.

Locator signals from the cockpit voice recorder have been picked up, but late last week bad weather had prevented recovery attempts. Meanwhile, apart from the hints of "heating" damage near the cockpit, the cause and precise location of the fire were unknown.

Source: Flight International