An Accident Investigation Board (AIB) study into the loss of a US Air National Guard Boeing F-15C on 2 November has indicated that the aircraft broke apart after suffering a catastrophic structural failure aft of its cockpit, says the US Air Force.

While the cause remains under investigation, the service had by 21 November returned 513 of its almost 700 F-15s to operational status following inspections conducted since they were grounded the day after the crash.

"The AIB is now focused on the area just aft of the cockpit and slightly forward of the [engine] inlets," says Air Combat Command (ACC) commander Gen John Corley. Conceding that there is a "degree of risk" in returning the F-15 to flight before the investigation has concluded, he notes: "Grounding a fleet of nearly 700 frontline aircraft has significant operational impact."

The USAF on 11 November instructed its F-15 units to return their aircraft to flight following safety inspections, and 219 of its 224 F-15Es have now been cleared. The first resumed combat operations over Afghanistan on 12 November, and the ACC concludes: "The F-15E is not susceptible to the same potential cause of the Missouri mishap."

Some 294 of the service's 442 earlier F-15s have also regained operational status.


Source: Flight International