Accident
A Saudia Boeing 747 departed New Delhi-Indira Gandhi Airport at 1833 LT on a flight to Jeddah with an intermediate stop in Dhahran, carrying 289 passengers and 23 crew members. The aircraft was instructed to climb to flight level 140 (14,000 feet) via route G452. Seven minutes after takeoff, while cruising at 14,000 feet, it collided with a Kazakhstan Airlines (Kazair) Ilyushin Il-76TD registered UN-76435. The Il-76 was completing flight KZA1907 from Shymkent with 27 passengers and 10 crew members and was descending to New Delhi Airport.
Collision and Crash
After the collision, both aircraft entered uncontrolled descents and crashed in an open field about 3 kilometers from Charkhi Dadri, approximately 80 kilometers west of New Delhi-Indira Gandhi Airport. Both aircraft were destroyed by impact forces and a post-crash fire. All 349 occupants on both aircraft were killed.
Probable Cause
The investigation determined that the collision resulted from the failure of the Kazakhstan Airlines crew to follow their assigned altitude of 15,000 feet while approaching New Delhi. Air traffic control had instructed the Il-76 crew to continue descending via route G452 to an altitude of 15,000 feet, while the Saudia 747 was cleared to 14,000 feet on the same route. For unknown reasons, the Kazair crew continued descending below flight level 150 without clearance, leading to a head-on encounter. In the minutes before the accident, both flight crews had been notified by ATC about the presence of other traffic.