The FAA has provided additional information and extended the comment period on a proposed airworthiness directive (AD) affecting thousands of Continental engines with aftermarket ECi cylinders. The move follows a request filed by AOPA and six other organizations last month.
On Sept. 26, the FAA announced a 60-day extension to the comment period on the proposed AD affecting ECi cylinders used as aftermarket replacements on Continental Motors 520 and 550 engines. The agency also added more detailed information to the docket, including a white paper and risk analysis.
The move followed an Aug. 30 letter from AOPA asking the FAA to withdraw the NPRM or provide supporting information to justify the proposal and extend the comment period by 120 days. Other signatories to the letter included the American Bonanza Society, Cessna Pilots Association, Experimental Aircraft Association, National Air Transportation Association, Savvy Aircraft Maintenance Management Inc., and the Twin Cessna Flyer organization.
“The additional information and time are steps in the right direction, but we still question the need for and the extent of the FAA’s proposed action regarding the cylinders,” said Rob Hackman, AOPA vice president of regulatory affairs. “This proposal far exceeds previous National Transportation Safety Board (NTSB) recommendations.”
The proposed AD recommends the repetitive inspection and early retirement of affected cylinders. It also would prevent new installations of the cylinders in question. But in February 2012 the NTSB issued more conservative recommendations, calling for repetitive cylinder inspections and the removal of cylinders with serial numbers manufactured between May 2003 and October 2009 once the affected engine reached its recommended time between overhauls (TBO).
The FAA estimates the proposed AD would cost $82.6 million and affect 6,000 aircraft with certain Airmotive Engineering Corp. replacement cylinder assemblies marketed by Engine Components International Division, better known as ECi. But AOPA and others are concerned that costs could actually go much higher and that the replacement of thousands of cylinders in the field could ultimately compromise, rather than enhance, pilot safety.
AOPA is reviewing the new information provided by the FAA and will file formal comments in advance of the Dec. 11 deadline.