WASHNGTON (AFNS) — F-35 Lightning IIs were cleared for flight Feb. 28 following a temporary suspension after a cracked engine blade was found in a test aircraft earlier in the month.

A .06-inch crack was discovered in a third-stage turbine blade in a test aircraft at Edwards Air Force Base, Calif., Feb. 19. Third-stage blades are located deep inside the engine.

A thorough series of tests on the blade concluded prolonged exposure to high-heat levels and other operational stressors on the engine were contributing factors. Edwards AFB is home of the service’s major flight test wing, where aircraft undergo rigorous testing.

“As with any new weapons system, we expect to learn things about the aircraft and the system over time and we are doing just that,” said Col. Andrew Toth, the 33rd Fighter Wing commander at Eglin AFB, Fla., where F-35 pilot and maintenance training began in January.

After the crack was found, all F-35 engines were inspected and no additional cracks or signs of similar engine stress were found.

Despite not being able to fly during the recent suspension, teams at Eglin AFB continued training in a state-of-the-art training center.

“Due to the fidelity of the simulators, approximately 50 percent of the core syllabus flights for the F-35 training program are accomplished virtually,” Toth said. “Any additional time in the simulator gives pilots an opportunity to practice more emergency procedures and improve their capabilities.”

The training center has electronic classrooms for maintainers, actual-size, mock-up cockpits and weapons bays. On the flightline, maintainers continued to hone their skills on the advanced, stealth fighter.

In a recent interview with The Washington Post, Lt. Gen. Frank Gorenc explained why the F-35, which will be built for the U.S. Air Force, Navy and Marines, and eight allies, is needed.

“Enemy threats are evolving. Their surface-to-air missile technology is evolving,” he said. “So that’s why fifth-generation technology is such a thing and that’s the promise of the F-35.”

Gorenc said aircraft like the F-16 Fighting Falcon and A-10 Thunderbolt II are far more vulnerable in “contested environments” because they are not stealth aircraft.

The general also explained the advantage of going to war with coalition partners that train with and fly the same aircraft.

“The ability to deal with coalition partners that operate the same equipment, that will probably adopt the same tactics, techniques, procedures, that will be involved in the same logistics concept,” Gorenc said, “That’s very important because when you have a coalition partner that is operating the same equipment, there are so many things in the joint fight that become much easier to do than you would expect.”

Former Defense Secretary Leon Panetta said July 18, the F-35 is critical to a future defense strategy that depends on agility, flexibility and the ability to stay on the cutting edge of technology.

“We’re committed to all three (F-35) variants,” Panetta said, “because we think each of the forces will be able to use that kind of weaponry for the future so that we can effectively control the skies as we confront the enemies of tomorrow.”

(Chrissy Cuttita at Eglin AFB and Cheryl Pellerin with American Forces Press Service contributed to this report.)

Source and photo: USAF