Aviation View April 2023

12 AVIATION VIEW MAGAZINE VOLUME 3, ISSUE 1 the critical crack length—the length at which the crack reduces the capability of the structure below that provided in the certification basis—is smaller in the later Model 210-series airplanes.” While the FAA did not entirely close the door on alternative methods of compliance, it rejected arguments that the AD should mirror a 2020 AD issued to address spar corrosion in Piper Aircraft PA–28 and PA–32 models. “The unsafe condition on the Model 210-and 177-series airplanes addressed by this AD involves both corrosion and cracking,” the agency wrote. “The FAA cannot use an evaluation similar to the one used for the Piper airplanes to draw the same conclusions or correlations to the unsafe condition addressed by this AD, as the unsafe condition associated with AD 2020-26- 16 [applicable to Piper airplanes] is primarily associated with fatigue cracking concerns.” AOPA continues to monitor the effects of age and corrosion across the general aviation fleet, and encourages owners to remain engaged in the process. Information that aircraft owners provide to AOPA (in addition to the reports required by the FAA) will help bolster future advocacy on behalf of aircraft owners against mandating inspections and other measures not supported by data indicating they are needed in the interest of safety. Source, aopa.org, Jim Moore, First Published Feb 16, 2023 Out of the 211 Model 177-series reports received by the FAA as of January 13, 2023, 120 have reported corrosion,” the agency wrote in the final AD. “Of those, at least 14 were removed from service due to corrosion or damage.” None of the later-model Cessna 210s inspected to date had spars taken out of service due to corrosion too severe to grind down and leave enough structure to remain in service, the FAA noted, though two Cessna 210 spars were removed from service due to damage. Just under 7 percent of the newer 210s had any corrosion found on inspection. Among the older Cessna 210s, the rate of corrosion discovery was much higher—47 percent. The FAA noted, however, that while the rate of corrosion discovery was lower, the newer Cessna 210 models are more susceptible to spar failure if the structure becomes compromised: “Analysis completed by Textron revealed that later Model 210-series airplanes, due to their weight and configuration, demonstrate higher stress levels in operation when compared to earlier Model 210-series airplanes. Therefore,