Forgotten Flashlight Causes $4 Million In F-35 Engine Damage

A maintenance error caused nearly $4 million in damage to a $14 million engine that powers a U.S. Air Force-owned, Lockheed Martin F-35A at Luke AFB, Arizona on March 15, the service announced on Jan. 19.

During a test run on the ground, the Pratt & Whitney F135 engine ingested a flashlight left inside an inlet during a maintenance inspection, according to an Accident Investigation Board report released by the Air Education Training Command (AETC).

The flashlight was left inside the engine inlet by a maintenance worker who conducted a final inspection, the report says. A different maintenance worker later ran an engine test, but failed to perform a required check prior to ignition, the report adds.

The incident caused more damage than could be repaired locally. The Air Force sends high-power modules that need advanced repairs to the F135 Heavy Maintenance Center at Tinker AFB, Oklahoma.

The report faulted the maintenance worker for not performing a required check of the engine tools before running the test. But the board also cited a deficiency with the F-35 program’s Autonomic Logistics Information System (ALIS) for contributing to the incident.

Maintenance workers must update checklists and inspection reports into ALIS, but the system’s hardware is not on the flight line. Workers download the latest maintenance data onto portable maintenance units to take to the aircraft on the flight line, but the downloads do not always work.

In the absence of reliable data on the flight line, units have turned to local “best practices” that are not compliant with official F-35 maintenance procedures, the report says. In this case, the local unit requires the person performing the engine test to complete the final check of maintenance equipment. The tester  might not necessarily be the worker who performed the last inspection, the report says.