Six aviation groups, including AOPA, EAA and the National Air Transport Association, have asked the FAA to publish the data and analysis that led to the agency’s proposal to require thousands of aircraft owners to inspect and perhaps replace certain ECi engine cylinders. The letter also requests that the FAA either withdraw its NPRM until that information is provided, or extend the comment period 120 days from the time additional information is provided. “To date the FAA has provided no supporting or substantial data of any kind to the docket to back its proposed action,” says the letter (PDF).
The letter also notes that the FAA’s own AD manual states that the AD docket “must contain any documents that support the 14 CFR part 39 action.” The proposed AD would affect about 6,000 aircraft, requiring repetitive inspections and the replacement of many cylinders. It would cost operators an estimated $82.6 million. “The early retirement of cylinders goes well beyond the February 2012 safety recommendation of the National Transportation Safety Board,” says the letter. The letter was also signed by representatives of the Cessna Pilot Association, the Twin Cessna Flyer, and Savvy Aircraft Maintenance Management. As of Monday, 361 comments had been posted to the FAA docket.