On July 27, 2022, the FAA proposed a new airworthiness directive (AD) that would require repetitive inspections of turbocharged, reciprocating engine-powered airplanes and helicopters, and turbocharged, reciprocating engines with “spot-welded, multi-segment v-band couplings at the tailpipe to the turbocharger exhaust housing flange.” Under the proposed AD, the clamps/couplings would be inspected annually, regardless of their accumulated time-in-service (TIS) and a life limit for the components would be established by removing them from service every 500 hours TIS. Since it is a proposed AD, not final, the FAA is requesting comments from the public by November 4, 2022.
According to the preamble in the notice of proposed rulemaking (NPRM), the NTSB has made seven recommendations regarding the components since 1974. Additionally, there are 10 ADs already on the books, plus an additional 11 special airworthiness information bulletins (SAIBs) addressing the components as installed on various turbocharged piston engines, whether installed at the time of production, under a supplemental type certificate (STC) or other means. The FAA said, “In spite of these efforts, failures continue to occur and the number of significant safety events continues to increase.”
