What happened
On October 10, 2015, a Boeing 767-300, operated by Japan Airlines Co., Ltd. (registration JA8364), was on final approach to Runway 34 at Kagoshima Airport. During the descent, a Britten-Norman BN-2B-20, registered JA80CT and operated by New Japan Aviation Co., Ltd., intercepted the flight path of the larger jet. The smaller aircraft approached from the left and below, cutting directly in front of the airliner. The pilot of JA836 and immediately initiated an evasive go-around to avoid a mid-air collision. At the moment of closest proximity, the two aircraft were separated by only about 10 meters horizontally and 250 feet vertically.
The investigation
The JTSB investigation focused on the communication between the air traffic controller and the pilots of both aircraft. The investigation established that the controller had instructed the pilot of JA80CT to "FOLLOW" preceding traffic. However, at the time, there were multiple aircraft in the sequence. The investigation examined radar tracks, flight recorders, and radio communications to determine why the smaller aircraft entered the path of the Boeing 767.
Investigators also looked into the controller's monitoring of the situation. While a second controller in the tower had raised concerns about the movement of JA80CT, the primary controller remained convinced that the aircraft was following the correct lead aircraft, as the pilot of JA80CT had reported seeing traffic in sight.
Findings
- The pilot of JA80CT mistakenly identified a DHC-8 aircraft on final approach as the intended lead aircraft, leading them to enter the final approach path behind the wrong plane.
- The pilot of the BN-2B-20 failed to verify if the aircraft they sighted matched the specific type and location information provided by the tower.
- The air traffic controller failed to provide the specific landing sequence number, which contributed to the confusion.
- The controller's reliance on the pilot's verbal confirmation without secondary verification via radar or direct radio inquiry prevented the error from being caught sooner.
- The pilot of JA80CT was experiencing reduced concentration due to personal stressors from earlier that day.