Two large jets came rather too close for comfort.
The flights and aircraft involved
The near mid-air collision took place on January 31st, 2001, in airspace near the Japanese city of Yaizu. One of the aircraft involved was a Boeing 747-400D, registered as JA8904. The aircraft’s ‘D’ suffix indicates its high-density layout for use on domestic flights. This remains a common practice with widebodies in Japan, due to its busy domestic network. In this instance, the aircraft was operating a domestic service for Japan Airlines from Tokyo Haneda to Naha. It had 411 passengers and 16 members of crew onboard.
Meanwhile, a jet that the 747 was set to cross paths with (at different altitudes) was JA8546. This McDonnell Douglas DC-10-40 was flying from Gimhae, South Korea to Tokyo Narita, and had 250 people onboard. This figure consisted of 237 passengers and 13 crew.
The DC-10 was operated by Japan Airlines. Photo: Guido Allieri via Wikimedia
A near miss
The Naha-bound Boeing 747-400D departed from Tokyo Haneda at 15:36 local time, and began climbing towards its planned cruising altitude of 39,000 feet. The flight plans of it and the Gimhae-Tokyo Narita service meant that the plane’s paths were set to cross en route, but 2,000 feet apart. This is a standard amount of vertical separation above 29,000 feet.
Around 20 minutes into the 747’s journey, its drinks service commenced. It was at this point that it and the DC-10 began to lose their planned separation. As a result, the aircraft’s respective Traffic Collision Avoidance Systems (TCAS) advised the 747 to climb, and the DC-10 to descend. This would have ensured sufficient separation at the moment of passing. However, while the DC-10 descended as instructed by the TCAS, so did the 747.
This was due to a conflicting instruction given in error by an air traffic controller. As a result, the jets lost separation and came within less than 450 feet of colliding. Thankfully, an evasive maneuver by the 747, lasting two seconds in visual proximity of the DC-10, prevented a crash.
Photo: Goran tek-en via Wikimedia
Evasive maneuvers cause injuries
The two aircraft had a combined 677 passengers and members of crew onboard. As such, a collision between the two could potentially have resulted in a significant catastrophe and hundreds of fatalities. The DC-10 continued to Tokyo Narita as planned. Meanwhile, the evasive maneuver used by the 747 to avoid the collision resulted in 100 injuries onboard. Nine of these were serious, and included broken bones.
Unbelted passengers and drinks carts were thrown around the cabin by the maneuver, causing minor damage. As such, the flight returned to Tokyo Haneda, landing just under an hour later. An investigation resulted in suspended prison sentences for the air traffic controllers. The process took years, with the Supreme Court upholding the convictions in 2010
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