AD Affecting Many Training Aircraft Related To Wing Spar Failure

The FAA has issued a Notice of Proposed Rulemaking that will expand the models of Piper aircraft that are subject to the Airworthiness Directive (AD) adopted by the FAA in January 2021.

The AD requires wing spar cap inspections and was prompted by an accident involving wing separation on a Piper Model PA-28R-201 Arrow III. The issue is primarily found in aircraft used in flight training and other aircraft used predominantly in high-load flight regimes.

An investigation by the NTSB revealed a fatigue crack in a visually inaccessible area of the lower main wing spar cap. The original AD included Piper models with similar main wing spar structures as the Arrow III. Based on a compilation of airplane usage history, the FAA determined that only aircraft with a higher risk of fatigue cracks, such as those being used in flight training should be subject to the inspection requirements proposed in that AD.

The initial AD also mentioned that it considered those requirements to be “interim” in nature and was considering further rulemaking.

Since then, the FAA evaluated inspection reports submitted by operators and determined that wing spars in additional Piper models should be inspected. This AD would require a review of aircraft maintenance records to determine if an eddy current inspection of the lower main wing spar bolt holes was done and depending on the result, doing a one-time eddy current inspection of those bolt holes for cracks and replacing any cracked main wing spar.

All of the initial and newly-added models of Piper aircraft covered by the AD and the NPRM are available at the link below.

FMI:  www.federalregister.gov/