Worst Mid-Air Crash in Aviation History part 2

Around 6:23 PM, Flight 1907 reached a waypoint west of Delhi called LUMKA. Waypoints function like intersections in the sky, where different airways cross. From there, the Kazakh flight was cleared to descend from 25,000 feet to 20,000 feet as it joined the “Delhi STAR” arrival route.

Meanwhile, after takeoff, the Saudi Boeing 747 was cleared to climb to 10,000 feet, and later to 14,000 feet. Both aircraft were now on the same flight path but separated by 1,000 feet vertically.

The air traffic controller on duty was V.K. Dutta. His responsibility was to maintain safe separation between the two aircraft.

At 6:34 PM, the Kazakh aircraft was cleared to descend further to 15,000 feet. Two minutes later, the Saudi aircraft was cleared to climb to 14,000 feet. That meant they were flying toward each other on the same route with only 1,000 feet of vertical separation.

At 6:38 PM, the Saudi crew reported reaching 14,000 feet and requested further climb clearance. The controller instructed them to maintain 14,000 feet because opposite traffic—the Kazakh aircraft—would cross above them.

The Kazakh crew consisted of a captain, first officer, flight engineer, navigator, and a radio operator. The radio operator was crucial because the crew primarily spoke Russian, while ATC instructions were given in English. His job was to translate ATC communications into Russian.

At 6:39 PM, the Kazakh aircraft reported that it had descended to 15,000 feet. However, radar later revealed that the aircraft was actually at about 16,348 feet and still descending.

The controller informed them of traffic ahead: a Saudi Boeing 747 at 14,000 feet, approximately 8–10 nautical miles away, and instructed them to report if they had the aircraft in sight.

The message was not clearly understood at first, and clarification was requested. By the time the information was correctly translated and processed in the cockpit, it was too late.

Moments later, a U.S. Air Force cargo aircraft in the vicinity reported seeing a massive explosion in the sky.

The Kazakhstan Airlines Il-76’s left wing struck the left wing of the Saudi Boeing 747. Both aircraft lost critical structural components. The Boeing 747 broke apart in the air and crashed near Dhani village in Haryana. The Il-76 went into a flat spin and crashed near Birohar village.

All 349 people on board both aircraft were killed.

The investigation revealed multiple contributing factors. The Kazakh aircraft had descended below its assigned altitude of 15,000 feet to 14,000 feet—the same level as the Saudi aircraft. There may have been misunderstanding of the instruction to “maintain 15,000 feet.” Translation delays and language barriers likely played a role.

There were also shortcomings in air traffic control procedures. When two aircraft are on reciprocal headings along the same flight path, a vertical separation of 2,000 feet is recommended. However, only 1,000 feet was maintained. Additionally, at that time, Delhi’s radar system displayed aircraft positions but did not provide reliable altitude information.

This devastating accident led to major changes in global aviation safety. One of the most significant was the mandatory installation of TCAS (Traffic Collision Avoidance System) on large commercial aircraft. TCAS can automatically issue collision-avoidance advisories to pilots.

Furthermore, the International Civil Aviation Organization (ICAO) strengthened English language proficiency requirements for pilots worldwide. Radar systems were also upgraded to provide both distance and altitude data.

The 1996 mid-air collision over Delhi remains one of the deadliest aviation disasters in history—a tragic reminder of how small misunderstandings and procedural gaps can lead to catastrophic consequences.