Sir, - The dreadful crash off Canada of the Swissair plane is at present a mystery; but perhaps it is similar to a crash at Shannon many years ago.
It has been stated that no explosion seems to have occurred in the aircraft, yet many people ashore five miles away claim to have heard an explosion like thunder. The box recorder stopped recording at 10,000 feet. The plane itself is broken up in to pieces no larger than a car roof. There was no distress call from the aircraft (there was a "Pan pan" call which is not a distress call but a possible emergency call to be followed by "Mayday, Mayday" for a real distress). The crew never got around to that even though they appeared to have the aircraft under full control until overtaken by sudden dire disaster.
It is known that the aircraft was dumping fuel and descending while flying in circles. This may well have been the cause of the disaster, as happened at Shannon all those years ago. Having dumped over 20 tons of fuel it is likely that in descending and circling, the plane flew back into its own dumped fuel with the resulting explosion. There would have been no time for a Mayday call, the recording box would have ceased doing so, and the aircraft would have tumbled to the sea with resultant complete break-up. - Yours, etc., Dermot C. Clarke,
Wilson Road, Mount Merrion, Co Dublin.