The FAA’s action would result in thousands of premature “top overhauls” where all six cylinders are removed and replaced in hundreds of general maintenance shops by A&P mechanics who are not engine specialists. Industry experience shows that there is a substantial risk of catastrophic engine failure following such top overhauls. All eight through-bolts that clamp the crankcase halves together are un-torqued, opening the door for main bearing displacement and other potentially catastrophic issues. In addition, the replacement cylinders are then broken in “in the field” rather than on the test stand in an engine shop, which often leads to improper break-in and excessive blow-by that can overheat and compromise the integrity of the head-to-barrel junction of the replaced cylinder.
Affected owners of these cylinders, and the organizations that represent their interests (AOPA, EAA, American Bonanza Society, Cessna Pilots Association, Cirrus Owners and Pilots Association, Twin Cessna Flyer, Malibu/Mirage Owners and Pilots Association, etc.), have 60 days to submit their comments to the docket #FAA-2012-002. The submission deadline is October 11, 2013. Detailed instructions for submitting docket comments can be found on the ECi website at www.eci.aero/NPRM, together with the NPRM itself, the research results and data AEC presented to the FAA and NTSB, and copies of correspondence with the FAA and NTSB.
We have all seen Airworthiness Directives (ADs) in the past that made us fear the further demise of general aviation. I can think back to 2003 when the outrageous proposal on 400 Cessna series...
AOPA's comments warn that the drastic course proposed by the AD is not supported by the data, could cost much more than the FAA estimates and has the potential to cause more safety problems than it...
The General Aviation community has mobilized to oppose a proposed AD on TITAN® brand 520/550 series cylinders produced between 2002 and 2009.