IL76/B747, New Delhi India, 1996 (LB LOS)
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The Official Accident Investigation Report is not available.
On 11 November 1996, an IL76 inbound to Delhi at FL150 was advised of an outbound Saudi B747 at FL140. The radio operator onboard the IL76 acknowledged the traffic advisory and asked how far away the Saudi aircraft was. ATC replied “traffic is at 8 miles now FL140”. Meanwhile the pilot and co-pilot were discussing the traffic information and it is suggested that the co-pilot only heard the last part of the ATC transmission “… now FL140” and interpreted it as a clearance to descend. Suddenly realising that the pilots had begun to descend, the radio operator shouted out “keep at FL150, don’t descend! ”. The, by now highly anxious, crew began to initiate a climb. 349 people died as a result of the subsequent collision; the worst disaster in India’s civil aviation history.
This was an accident caused by a classic Level Bust incident resulting from poor communication and a lack of coordination on the IL76 flightdeck.