New extension granted for life-limited Superior Air Parts cylinders

The extension, in the form of a global alternative method of compliance (AMOC) to AD 2014-05-29, was granted in response to a joint request made in February by the manufacturer and AOPA.

In an approval letter, the FAA required anyone using the AMOC to provide advance notice to the FAA as specified. All provisions of AD 2014-05-29 not specifically noted in the approval remain in force. The FAA allowed the AMOC to be transferable with the aircraft to another operator who operates the aircraft under U.S. registry.

Previous extensions of an original 12-year cylinder-replacement provision were granted for five years in 2014 and two years in 2018, applicable to aircraft powered by Continental's IO-520, TSIO-520, and IO-550 engines, and any other engine, such as the 470 series, with a supplemental type certificate for the same Superior Air Parts cylinder assemblies with more than 750 hours’ time in service on the cylinders.

The 2018 extension ended an effective grounding of some aircraft to which AOPA had objected on behalf of members. AOPA and Superior Air Parts noted at that time the significant cost savings the extension would provide those owners. Also, there had been no known accidents or incidents “resulting from cylinder head separation” since the AD was issued.

AOPA will continue to evaluate safety data and field experience when interacting with the FAA on issues related to the AD.