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.