FAA’s NPRM On Corrosion Concerns Includes Additional Cessna Singles

In March 2020, Flying reported on an airworthiness directive focused on corrosion concerns on most models of the Cessna 210. On Tuesday, May 11, the FAA published a Notice of Proposed Rulemaking (NPRM) that may broaden the scope of that original AD to include both the Cessna 210R and N models, as well as all models of the Cessna 177 Cardinal. An NPRM is a preliminary announcement of the FAA’s intentions that could lead to a new AD. The agency will base its final decision to proceed onto a new AD after reviewing the user comments that the NPRM is requesting.

This proposed AD was prompted by the May 26, 2019, in-flight break-up of a Cessna T210M in Australia—the result of fatigue cracking that initiated at a corrosion pit, as well as subsequent corrosion reports on other Model 210-series and Model 177-series aircraft. The T210 experienced a wing separation after the carry-thru spar failed, and a subsequent loss of control in-flight while performing low-altitude aerial survey work.

The proposed AD to address the unsafe condition on these aircraft would require visual and eddy current inspections of the carry-thru spar lower cap. Corrective action, if necessary, calls for the application of a protective coating and corrosion inhibiting compound (CIC), as well as reporting the inspection results to the FAA. If a crack is identified, the carry-thru spar must immediately be removed from service. The FAA requests to receive comments on this NPRM no later than June 25, 2021.