What happened
On October 3, 2019, at Misawa Airbase, a Japan Air Self-Defense Force F-2A, registration 93-8ally-8550, entered Runway 10 without authorization. At the time of the incursion, an Embraer ERJ 170-100STD, registration JA216J, operated by J-AIR Corporation, was on its final approach to the same runway after receiving landing clearance.
The pilot of the F-2A was taxiing for a solo instrument flight training mission. After being instructed to hold short of the runway, the pilot waited on taxiway B1. During this period, the pilot experienced a period of radio silence on the UHF frequency, leading him to believe his departure schedule would need to be revised.
At 12:47:06 JST, the air traffic controller notified the F-2A of a departure delay, stating that takeoff would be expected after the arrival of an E-170 on final approach. The pilot of the F-2A misinterpreted this information as a takeoff clearance and immediately increased power to move toward the runway. Simultaneously, the pilot performed a required radio report to a ground observer, which prevented him from hearing the controller's immediate corrective instruction to hold short. Because the landing clearance for the JA216J had been issued on a different frequency (VHF) than the one the F-2A pilot was monitoring (UHF), the pilot was unaware of the approaching aircraft. To avoid a collision, the controller ordered the JA216J to execute a go-around.
The investigation
The Japan Transport Safety Board (JTSB) examined air traffic control records, radar tracks, and video recordings. The investigation focused on the communication gap between the tower and the pilot, the use of different radio frequencies for military and civil aircraft, and the pilot's failure to follow standard communication loop procedures. The investigation also reviewed the pilot's psychological state regarding the training delay and his failure to visually scan the runway approach path.
Findings
- The pilot of the F-2A misunderstood the departure delay notification as an actual takeoff clearance.
- The pilot failed to listen to the controller's corrective holding instruction because he was preoccupied with reporting pre-flight procedures to a ground observer.
- The pilot did not visually confirm the final approach course for the arriving aircraft.
- The use of different radio frequencies (UHF for military and VHF for civil) meant the pilot of the F-2A had no information regarding the landing clearance issued to the Embraer.