The F-35 Joint Strike Fighter jet has been cleared to resume operations after being grounded last week due to a crack in an engine turbine blade, the F-35 Joint Program Offie (JPO) said Friday in a statement.
A cautionary flight suspension was announced Feb. 21 after a one-fifth inch crack was found on a 3rd stage engine turbine blade during a routine inspection at the F-35 Integrated Test Facility at Edwards AFB, Calif., the JPO said.
The crack was in an engine powering an Air Force F-35A conventional takeoff and landing (CTOL) variant used for testing at Edwards, but the suspension also affected the Marine Corps’ F-35B and the Navy’s F-35C variants (Defense Daily, Feb. 25). No additional cracks or signs of similar engine stress were found during inspections of the remaining F135 engine inventory. No engine re-design will be required. The F135 engine is developed by Pratt & Whitney, a division of United Technologies Corp. [UTX]
The Pentagon is currently examining a problem with a component of the F-35 that caused smoke in the cockpit during a flight Feb. 14. DoD said the incident involved a power system that controls oxygen and temperature in the cockpit, and components have been shipped to manufacturer Honeywell [HON] for evaluation. The issue is believed to be software related and “very minor,” the Pentagon official said (Defense Daily, Feb. 26).
The F-35B was cleared to resume flying in mid-February following a mid-January grounding (Defense Daily, Feb. 14). The problem was caused by poor crimping in the fueldraulic line, which is in the vectoring propulsion system specific to the short-takeoff and vertical-landing version flown by the Marines. The faulty ones were replaced.
The F-35 is developed by Lockheed Martin [LMT].