After receiving a report of undersized fasteners possibly being used during the construction of some Piper M600s, the FAA on Tuesday issued an airworthiness directive to address what it called an “unsafe condition.” The AD, effective July 25, 2018, is aimed at M600s serial numbers 4698004 thru 4698041.
The agency’s concern is focused on the cockpit canopy above the left and right side windows. The AD requires installation of a repair kit depending upon the results of a rivet inspection. The directive also requires inserting a temporary speed limitation in the pilot operating handbook, as well as a temporary placard. The agency believes failing to inspect for and correcting this problem should it be discovered could result in failure of the skin joint leading to a loss of cabin pressure and or a fuselage structural failure.
The FAA approved a one-time special flight permit that includes necessary fuel stops to allow affected aircraft to reach a Piper service facility for the inspection and repair. Until compliance is assured, the affected M600s may not be operated at greater than 230 kts calibrated airspeed.
The FAA’s estimate of inspection and repair indicate the AD (FAA-2018-0606) could be costly. The inspection could run about $6,300 while the actual repair work, if necessary, might cost an additional $200,000. A Piper spokesperson said, "“All costs associated with Service Bulletin 1318 B as well as the AD are fully covered by Piper Aircraft. Since the service bulletin was issued in early June (June 7), 22 of the 38 affected airplanes (60%) have already complied with the original requirements of the Service Bulletin / AD.”
Because there was no notice prior of the AD, the FAA is inviting comments to the rule by using a number of methods outlined in the “addresses” section of the AD.