FAA’s Proposed Airworthiness Directives Focus on PA-28 and PA-32 Wing Spars

EAA is evaluating two proposed airworthiness directives (ADs) published by the FAA, expanding the main wing spar inspections on Piper PA-28 and PA-32 single-engine aircraft. These proposals result from findings from the inspections required by AD 2020-26-16, which require wing spar inspections on some Piper aircraft models. Based on these findings, the FAA is proposing to expand the scope of aircraft needing inspections, modify the inspection intervals, and amend the formula used to calculate aircraft time triggering the inspections.

The proposed ADs are FAA-2024-2142 (comment deadline Nov. 7) and FAA-2024-2143 (comment deadline Nov. 4). Comments can be submitted to each proposed AD at www.regulations.gov.

AD 2020-26-16 was published in January 2021 and was prompted by the wing separation of a Piper Arrow used extensively in flight training and two additional NTSB reports of aircraft with similar wing spar issues. The AD requires aircraft with certain use histories, as determined by a formula that accounts for total time in service and 100-hour inspections, to undergo eddy current inspections on their wing spars.

According to the proposed ADs, the FAA and Piper received more than 2,800 bolt-hole eddy current inspection reports following the release of AD 2020-26-16. Of the total inspections, more than 100 reported a positive eddy current indication, with several including pictures of the bolt hole showing the source of the indication. Piper conducted further inspections in a study of 24 main wing spars with 20 having positive eddy current indications. Out of the 20 positive indications, three were identified as fatigue cracks, where one was confirmed by Piper, and two were confirmed by the NTSB. The inspections also resulted in indications that are likely not fatigue cracks but are a variety of anomalies in the bolt holes that the FAA also feels warrant further inspections.

Proposed AD FAA-2024-2142 modifies the formula for calculating the applicable time for eddy current inspections of the lower main wing spar bolt holes and, depending on the results, repairing or replacing any cracked main wing spars. It affects 10,665 airplanes and applies to the following models:

Proposed AD FAA-2024-2143 would require reviewing airplane maintenance records to determine if an eddy current inspection of the lower main wing spar bolt holes was completed. If no previous eddy current inspection has been completed, at 12,000 hours time in service, completing a one-time eddy current inspection of the lower wing spar bolt holes for crack(s), and depending on the results, repairing or replacing any cracked main wing spars. It affects 10,927 airplanes and applies to the following models: