FAA orders immediate spar inspection of 499 Piper aircraft
Certain Archer, Cherokee, Seminole, Seneca models affected
A manufacturing defect that weakens the wing spar was uncovered when a Piper airplane was repaired following a ground collision with a car. The FAA issued an airworthiness directive to immediately inspect an estimated 499 aircraft.
The AD published May 22 is effective June 6. It mandates inspection before further flight, and refences Piper Aircraft Service Bulletin 1413 (which is included in the online docket). It applies to various Piper Archer, Arrow, and Pilot 100 singles, as well as Seminole and Seneca V twins, in all cases by serial number, with an FAA-estimated cost of $85 (1 work hour) to inspect the rear wing spar attachment fitting to confirm the fastener hole is the correct diameter. If discrepancies are found, the AD requires additional inspection of the forward wing spar attachment fitting—and reporting findings (along with corrective action taken) to the FAA.
The AD does not mandate every element of the Piper Aircraft service bulletin issued in April: Corrosion inspection and remediation called for by the manufacturer is not required by the AD.
The required inspection includes measuring the diameter of the bolt holes to identify whether the manufacturing defect is present.
"A double-drilled bolt hole of the rear wing spar attachment fitting reduces its strength below its limit load with possible failure of the fitting, which can lead to load redistribution and result in possible failure of the primary wing structure. This condition, if not addressed, could result in separation of the wing and loss of control of the airplane," the FAA wrote.
The agency estimates the cost of repairs that may be required (if inspection reveals that the attachment holes are out of tolerance) will be up to $3,658 per aircraft, and $3,828 including the additional inspection and submitting the report.
