The FAA has published an Airworthiness Directive affecting an estimated 2,147 Cessna twin-engine airplanes, requiring the owners or operators of high time aircraft to inspect the spar caps, and if cracks are found, replace the carry-through spar. Sixteen models in the 400-series are listed in the AD, along with serial numbers for each type. If no cracks are found, the inspection must be repeated every 50 hours. If cracks are found, the airplane is grounded until the spar can be replaced. The FAA estimates the inspection will cost about $1,020, and the replacement of the spar, if needed, would cost about $73,000. The AD was prompted, the FAA said, by a report of a fully cracked lower forward carry-through spar cap. The cracks could cause the spar cap to fail in flight, resulting in a loss of control, the FAA says. The AD is effective Feb. 28.
The time allowed to do the inspection varies with the particular model and time-in-service for each airplane. The inspection cycles are triggered at 11,000 hours for some models, 12,000 hours for others and 15,000 hours for the rest. Operators are required to report the results of each inspection to the FAA. The FAA said it considers this AD an “interim action.” Textron Aviation is evaluating the inspection intervals, the FAA said, and also is designing a replacement carry-through spar cap from an improved material. “After the evaluations are complete and the design modification is developed, approved, and available, we may consider additional rulemaking,” the FAA said. The FAA also is accepting comments on the rule. Courtesy of AVweb.