Air Force grounds F-15s — again - Navy News | News from Afghanistan & Iraq - Navy Times

Air Force grounds F-15s — again

For the second time in less than a month, F-15 Eagles are grounded.

Air Combat Command announced today that A, B, C and D-model versions of the fighter would “stand down” for an indefinite period of time.

F-15E Strike Eagles, a larger and newer version of the fighters, are not grounded and continue to fly, ACC said.

Like the ordered grounding on Nov. 3, this decision stems from the Nov. 2 crash of a 27-year-old Missouri Air National Guard F-15C. That fighter broke apart between the cockpit and main fuselage as it flew an air-to-air combat training sortie.

Wednesday’s announcement comes 12 days after F-15 A-D units were told their jets could return to flight as each fighter passed a 15-hour-long inspection. As of today, about 90 percent of the F-15As, Bs, Cs and Ds had passed the inspection.

Air Combat Command spokesmen said the new concern involves cracks in metal supports called longerons near the cockpits. The longerons are metal rails that hold the fuselage of the aircraft together.

The latest decision to ground the jets was based on a metallurgical analysis of the jet that crashed Nov. 2. The investigation drew attention to the F-15’s upper longerons near the canopy of the aircraft that appear to have cracked and failed, ACC said.

Those longerons were covered in general by previous inspections but technical experts with the air logistics center assisting in the accident investigation board have recommended a specific inspection of the suspect area.

The F-15 program office at Warner Robins Air Logistics Center, Ga., is developing new inspection criteria for the jets. Originally manufactured by McDonnell Douglas, the A-models, the oldest of the service’s F-15s, have been flying since 1975 and were developed to replace the F-4 Phantom and take on the MiG-25. C-models came on line in the late 1970s. The B-model and D-model Eagles are two-seat trainer versions of the A and C planes.

Boeing, which purchased McDonnell Douglas a decade ago, delivered the last F-15 to the Air Force in 2004 and is now working to upgrade some of the older planes. The most recent model, the unaffected F-15E Strike Eagle, entered service in 1989 and is currently in use in Afghanistan.

Variants of the F-15 are also in use by the air forces of Israel, South Korea, Saudi Arabia, Singapore and Japan.

DISCUSS: The issues with the F-15s