SEPTEMBER 27, 2024 – Pacific Air Forces released the results of its investigation into an F-16C aircraft mishap that occurred near Kunsan Air Base, Republic of Korea, on Dec. 11, 2023.
On Dec. 11, 2023, at 8:42 a.m. local Korea Standard Time, an F-16C assigned to the 8th Fighter Wing at Kunsan AB, ROK, crashed due to loss of primary flight and navigation instruments during adverse weather conditions.
The Accident Investigation Board President found, by a preponderance of the evidence, the cause of the mishap was the aircraft experiencing an embedded GPS inertial navigation system failure, resulting in the loss of primary flight and navigation instruments, amid weather conditions which required a reliance on flight instruments to maintain aircraft control. The board president also identified the pilot’s subsequent reliance on the standby attitude indicator, which displayed readings contradicting other instruments, leading to spatial disorientation, as substantially contributing to the mishap.
The board noted the absence of the GPS inertial navigation system failure in midst of the weather conditions may have prevented this mishap. The total destruction of the F-16 significantly limited the Accident Investigation Board’s ability to analyze physical evidence and determine the cause of the system failure.
Approximately 13 minutes after takeoff, while flying through dense cloud coverage, the aircraft’s primary flight and navigation instruments failed, resulting in horizon, or attitude, information being limited to the standby attitude indicator, which had been experiencing pitch and bank errors.
Without a reliable horizon indicator, the pilot experienced disorientation but continued to fly with navigation and altitude information provided by a wingman, attempting to find cloud-free sky at a lower altitude. However, mismatch in data between the standby indicator, still experiencing errors, and the wingman’s cues resulted in further spatial disorientation at an increasingly low altitude and the pilot made the decision to eject.
The ejection was successfully accomplished at 1,730 feet mean sea level and the aircraft impacted the Yellow Sea.
The incident did not result in any serious injuries or fatalities, but it did result in the total loss of the aircraft.
In accordance with Air Force Instruction 51-503, Aerospace and Ground Accident Investigations, the accident investigation board conducted a legal investigation to inquire into all the facts and circumstances surrounding the accident, prepared a publicly-releasable report, and obtained and preserved all available evidence for use in litigation, claims, disciplinary action and adverse administrative action.
A copy of the full report may be viewed here.
U.S. Pacific Air Forces also conducted a thorough safety investigation to ensure any lessons learned from this mishap were immediately implemented to prevent future incidents. Air Combat Command implemented increased, continuous training for pilots to recognize and correct flight instrument system issues during emergency scenarios, emphasizing the importance of understanding these systems and their limitations across the F-16 fleet. Additionally, the Air Force is working to limit the impacts of temporary power fluctuations on flight instrument systems in the F-16.
Seventh Air Force senior leaders continue to prioritize the safe operation and readiness of all U.S. Air Force F-16s on the Korean peninsula with rigorous safety and inspection standards.
The investigation for one other F-16 incident in January 2024 is still being conducted and its results will be published as soon as they are available for public release. Preliminary findings from the January incident do not indicate it was related to the previous two events.
Seventh AF remains prepared, if called upon, to fight tonight and provide airpower to deter aggression and maintain the Armistice, defend the Republic of Korea, and defeat any attack against the ROK-U.S. Alliance.
Story by Maj. Rachel Buitrago
7th Air Force