AD On Cessna 210 Fleet, ITDM Pilots Get a Chance

Wing spar corrosion is the concern for most of the Cessna Centurion fleet. Meanwhile, the FAA updates the protocol for diabetic pilots.

After a Cessna T210M experienced an inflight breakup in Australia last year, the FAA has issued AD 2020-03-16, effective March 9, 2020, for the visual and eddy current inspections of the carry-through spar lower cap. The AD isn’t isolated to M-model Centurion, but also applies to the 210G, T210G, 210H, T210H, 210J, T210J, 210K, T210K, 210L and T210L series.

According to the AD, corrective action includes replacement of the carry-through spar (if necessary), application of a protective coating and corrosion-inhibiting compound and also reporting the inspection results to the FAA. In the accident airplane, it was fatigue cracking that initiated at a corrosion pit (severe corrosion was also reported on other Centurions) that ultimately caused the wing failure. 

Expect some teardown just to accomplish the initial inspection. This requires removal of the headliner, the oxygen plumbing and head protection foam pads from the spars and anything else in the way of an unobscured inspection of the full strut. 

The issue shouldn’t be a surprise for 210 owners. The FAA issued an airworthiness concern sheet (ACS) on June 27, 2019, advising owners and operators of the accident and requesting relevant information about the fleet. Following the ACS, the FAA received reports of widespread and severe corrosion of the carry-through spar—something that should be a concern for anyone shopping the 210 market.

Moreover, investigation identified that these early-model airplanes were manufactured without corrosion protection or primer, increasing their susceptibility to corrosion. In the discussion portion of the AD, the FAA says the design of these early-model airplanes, where the upper surface of the spar is exposed to the environment, allows a pathway for moisture intrusion. Model 210-series airplanes were also delivered with foam installed along the carry-thru spar lower cap. The foam traps moisture against the lower surface of the carry-through spar cap, which can increase the development of corrosion, says the FAA.

For more compliance data, see Textron Aviation Mandatory Single Engine Service Letter SEL–57–08, Revision 1, dated Nov. 19, 2019 (SEL–57–08 R1). This service information contains instructions for visually inspecting the carry-thru spar for corrosion, damage and cracks and for completing an eddy current inspection. This service information also specifies applying protective coating and corrosion inhibiting compound.

We covered the Cessna 210 series in the February 2017 Aviation Consumer Used Aircraft Guide.  


If you do and need it to control your diabetes and want FAA medical certification higher than Class 3 criteria, there’s good news. The FAA published a notice in the Federal Register on risk assessment for the Diabetes Protocol given the progress that’s been made in treating and monitoring the disease. 

Essentially it says that ATP and commercial pilots with insulin-treated diabetes mellitus (ITDM) might receive first- and second-class special-issuance medical certification for ATP and commercial flying privileges. 

Worth mentioning is that since 1996 the FAA has allowed special-issuance medical certification for private pilots seeking third-class medical certification, but that just wasn’t good enough for ATP or commercial flying duties. 

If you’re a diabetic on insulin and even if you only want a third-class medical, you can still apply under the old FAA protocol or this new one. For more, contact Marcia Alexander-Adams at [email protected].  

Larry Anglisano
Editor in Chief Larry Anglisano has been a staple at Aviation Consumer since 1995. An active land, sea and glider pilot, Larry has over 30 years’ experience as an avionics repairman and flight test pilot. He’s the editorial director overseeing sister publications Aviation Safety magazine, IFR magazine and is a regular contributor to KITPLANES magazine with his Avionics Bootcamp column.