First Swiss jet disaster left its mark

Fifty years ago, a Swissair plane flying from Zurich to Rome crashed shortly after take-off, killing all 80 people on board - more than half of them residents of one Swiss village. It was the first major jet disaster in Swiss aviation history.

Flight SR306 took off from Zurich Airport in thick fog shortly after six a.m. on September 4, 1963. Only four minutes later, as the plane – a French-built Caravelle – reached its cruising altitude, people on the ground noticed a trail of smoke coming from the left side of the aircraft. Shortly afterwards a long flame appeared on the left wing.

Several minutes later the plane began to descend from 2,700 metres, turning slowly before quickly losing altitude. It then went into a steep dive. Only nine minutes after taking off the jet crashed on the outskirts of the village of Dürrenäsch, 35 kilometres from Zurich airport.

The probable cause of the accident was a fire resulting from the overheating of the brakes during the taxiing phase.

The brakes overheated after the pilots applied full engine power during taxiing on the runway in dense fog. This caused wheels to burst. When the landing gear was retracted after take-off, hydraulic lines were damaged.

Spilt hydraulic fluid then caught fire when it came into contact with the overheated landing gear. The fire damaged the gear bay, then spread to the wing. Finally, the aircraft became impossible to control, leading to the crash. 
(SRF/swissinfo.ch)