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USAF F-15s back on ground with new crack fears
By Stephen Trimble
The US Air Force has detected a possibly "catastrophic" design weakness in the Boeing F-15A-D. Air Combat Command on 28 November grounded all F-15s excluding the F-15E Strike Eagle.
Preliminary findings from an investigation of an accident on 2 November - in which an F-15C disintegrated in mid-air - revealed cracks in the F-15's upper longerons near the canopy seal.
Moreover, recent inspections found cracks in the same area on two other F-15s. According to the USAF, simulations by Boeing indicate such cracks could cause "catastrophic failure".
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