Bombardier CL-600-2B19 CRJ, West Grove, Pa., Oct. 17, 2005–The NTSB blamed the accident on the separation of the exhaust nozzle due to inadequately designed attachment hardware.
Climbing through 15,000 feet after taking off from Philadelphia International Airport, the crew of the US Airways Express Canadair Regional Jet heard a “small thud.” Thinking it might have been wake turbulence, they continued to their destination, where they found the left engine exhaust nozzle and fairing were missing. The nozzle was found about 26.5 nm from PHL, near West Grove, Pa. The nozzle’s attachment hardware was missing and the bolt holes were elongated and showed evidence of fretting.
The exhaust nozzle manufacturer had issued a Service Bulletin in 2003 to address “exhaust nozzle bolt attachment failures.” It called for the replacement of existing hardware with “new, improved hardware.” The operator of the accident airplane had not complied with the Service Bulletin.