What happened
A non-scheduled passenger service operated by Hermes was traveling from Blackbushe Airport in England to Singapore, with scheduled stops in Karachi, Delhi, and Calcutta. During the final stages of a radar-assisted approach to runway 01R at Dum Dum Airport, the Hermes aircraft collided with a Dakota positioned on runway 01L at approximately 00:00 GMT.
The impact resulted in the total destruction of the Dakota aircraft. All four crew members aboard the Dakota were killed in the accident. The Hermes aircraft also suffered significant damage during the collision, rendering it beyond repair. Among the passengers on the Hermes, two individuals sustained injuries.
Findings
The investigation determined that the commander of the Hermes aircraft made a critical error by reducing radio transmissions during the approach. This decision, combined with continuing the descent under visibility conditions that prevented the pilot from clearly identifying the assigned runway, led to the aircraft mistakenly landing on runway 01L instead of the instructed runway 01R.