WASHINGTON — The Air Force will probably order dozens of its F-15 fighter jets permanently grounded because of crucial structural flaws, significantly reducing the number of planes available to protect the United States, officials said Tuesday.
After one of the jets broke apart during a simulated dogfight in November, Air Force officials grounded the entire F-15 fleet, nearly 700 planes in all, fearing such a defect. The newest versions of the fighter jets were allowed to resume flying shortly afterward, but 440 of the older model F-15s have remained out of service.
The Air Force plans to allow about 260 of the remaining grounded planes to return to duty today. But about 180 more will remain idle because of suspected structural flaws.
"Many of them may never fly again," a senior Air Force officer said. The officer, like others interviewed for this article, spoke on condition of anonymity because results of the investigation are not due to be made public until today.
Long the nation's most sophisticated front-line fighters, the F-15 are gradually being replaced; many are up to 30 years old. The Air Force still relies on F-15s to protect the continental U.S. and to fly combat missions abroad. Newer model F-15Es are used in combat in Iraq and Afghanistan and were the first of the grounded planes to resume flying after the mishap in November.
The problems with the F-15, Air Force officials argue, have increased the need to purchase more F-22s, swift and stealthy but expensive new fighter planes. Air Force officials characterized the grounding of the F-15s as even more serious than if the Army had to take a large portion of its battle tanks out of service in Iraq.
"This is grave; we've had a heart attack," said a senior Air Force official. "Two hundred of our air superiority aircraft are on the ground, and we are acting like it is business as usual."
An investigation of the Nov. 2 crash shows the F-15 that broke apart over eastern Missouri had a fault in a crucial support component called a longeron, a structural beam that serves as part of the spine of the aircraft. F-15s have four longerons around the cockpit.
Air Force officials have not yet learned how a defective beam came to be installed in the plane, which was manufactured in 1980. But Air Force officials emphasized that the age of the airframe, combined with the faulty part, puts the older F-15s at risk.
