What happened
On 6 November 2019, during a night Suppression of Enemy Air Defense (SEAD) Flight Lead Upgrade mission, an F-16CM, tail number 90-816, released an inert GBU-12 bomb that landed outside the intended training area. The aircraft, assigned to the 14th Fighter Squadron, 35th Fighter Wing based at Misawa Air Base, was conducting a solo sortie after initial mission planning had suggested a larger formation.
While attempting to deploy the weapon within the Draughon Range, the pilot encountered heavy cloud cover that obscured the tactical target. To complete the training objective, the pilot requested assistance from another flight, Shinzo 1 and 2, to guide the weapon release. Although the assisting aircraft successfully acquired the target visually, a breakdown in communication occurred during the data transfer process. The pilot selected a Sensor Point of Interest (SPI) that was approximately 3.4 miles away from the actual authorized target. Consequently, the inert bomb followed a ballistic path that resulted in it impacting private property near the northern edge of Lake Ogawara. There were no deaths or injuries and no damage to structures or government property.
The investigation
The Air Force Accident Investigation Board examined the sequence of events leading to the off-range impact, focusing on the coordination between the mishap pilot and the assisting flight. The board reviewed cockpit communications, weather conditions at the time of the release, and the technical functionality of the aircraft's targeting systems. The investigation specifically looked into why the pilot failed to verify that the selected SPI matched the target identified by the wingman.
Findings
- Pilot error was identified as the primary cause, specifically the failure to positively identify and confirm that the selected SPI corresponded to the authorized target within the range boundaries.
- A lack of standardized communication and a failure to use concise service terminology prevented the crew from verifying the target coordinates.
- The pilot experienced channelized attention on the aircraft's tactical display, which contributed to the breakdown in coordination with the instructor pilot.
- Adverse weather conditions, including night operations and scattered cloud layers, forced a reliance on external visual guidance, increasing the complexity of the task.
- The presence of a spuriously generated SPI coincided with the targeting request, contributing to the confusion between the intended target and the erroneous coordinate.