How An F-35's Engine Was Taken Out By A Simple Flashlight

According to a report by the Air Force Aircraft Accident Investigation Board, a flashlight took out one of the most advanced fighter jets in the Air Force's arsenal. This was not an intentional action. It happened during a routine maintenance check by a fully qualified 62d Aircraft Maintenance Unit crew. Unfortunately, it was irreparable damage to an engine that was worth $14 million on its own.

The F-35 Lightning II is an advanced piece of military technology capable of air-to-air combat and air-to-ground missions. Lockheed Martin designed the F-35 to deflect radar energy away from it, providing it with a higher probability of infiltrating enemy territory before detection. The United States Air Force officially adopted the F-35 Lightning II in 2016 with plans to replace the F-16 Fighting Falcon with it. It's a $78 million aircraft that can just as easily meet its end in the air against enemy aircraft or on the ground during routine maintenance. The Air Force's report details the events leading up to the mishap.

Always keep track of the tool kit inventory

In March of 2023, at Arizona's Luke Air Force Base, a maintenance team assigned to the 56th Fighter Wing ran a series of tests and installations on an F-35's propulsion system. According to the report, the three-person team installed a fuel metering valve into the engine fuel line and immediately followed up with a test to check for fuel leaks. The maintenance team reported no visual signs that would indicate a faulty test. After running idle for five minutes, the aircraft's computer system also failed to report a foreign object ingestion alert. That all changed once the maintenance team shut off the engine. While the aircraft powered down, the team heard abnormal noises inside the engine.

Once the team made note of the noise, they performed their post-operations servicing inspection to identify the cause. There was clear damage to the engine's blades, with one maintainer stating, "I believe [the engine] just ingested a flashlight." The team needed a flashlight to install the metering valve, which they missed during a tool kit inventory check before running their fuel leak test.

Luckily, nobody was injured during the procedure. The cost of leaving a foreign body in the engine of an F-35 ran the Air Force an estimated $3,933,106, according to the report. That's an expensive learning experience, but the maintenance team will most definitely conduct a more thorough tool kit inventory with all future assignments.