Your Cherokee's Wing Is Cracking Where No Inspector Can Look

On 4 April 2018, a Piper PA-28R-201 Arrow lost its left wing in flight near Daytona Beach, Florida, killing student pilot Zachary Capra and designated examiner John Azma. The airplane had passed an annual inspection 28 flight hours earlier with no discrepancies written up. The NTSB found that the sign off was accurate, and that the crack which brought the wing down had started inside the bore of a wing attachment bolt hole, in a location the Board stated would have prevented visible detection from the interior or exterior of the airplane. This video works through what the National Transportation Safety Board found in the wreckage of N106ER, why the existing inspection regime was never capable of finding the crack, and what the investigators discovered when they went back and examined the right wing, the one that was still attached. It also covers the sister ship at the same flight school that was found with a crack of the same size at the same bolt hole, and the nine other Arrows inspected in the weeks afterward that showed nothing at all. The second half deals with the regulatory response. Airworthiness Directive 2020-26-16 has been in force since February 2021, covering 5,440 US registered aircraft and requiring a high frequency eddy current inspection of two bolt holes once an airframe passes 5,000 factored service hours. In September 2024 the FAA proposed two further directives covering 21,592 aircraft, expanding the inspection to every inner surface bolt hole in the lower spar cap on both wings and introducing hard life limits on the spar for the first time. Those proposals remain unfinalised as far as can be verified. We also look at the arithmetic that decides which airplanes are affected. The factored service hours formula weights every hour flown outside a 100 hour inspection cycle at one seventeenth of an hour, which is why most private Cherokee owners concluded the 2021 directive was a flight school problem. The 2024 proposals move that divisor to three, and on some models to two. Six confirmed fatigue cracks were found in more than 2,800 inspections. The FAA, Piper Aircraft, AOPA, the EAA and a member of the NTSB do not agree on what that number means. Nothing here is legal or maintenance advice. Verify the airworthiness directives that apply to your specific aircraft with the FAA and a qualified mechanic. Chapters: 00:00 The Checkride That Never Landed 05:11 A Clean Sheet, Fourteen Days Out 08:34 The Crack Inside the Bolt Hole 13:39 The Wing That Held 17:54 Six Cracks and Twenty One Thousand Airplanes References: NTSB Aviation Accident Final Report ERA18FA120. National Transportation Safety Board. NTSB Investigative Update, ERA18FA120. National Transportation Safety Board. AD 2020-26-16, Piper Aircraft Inc. Airplanes. Federal Register, 15 January 2021. NPRM 2024-21209, docket FAA-2024-2143. Federal Register, 19 September 2024. NPRM 2024-21652, docket FAA-2024-2142. Federal Register, 23 September 2024. SAIB 2022-20, Wing Spar Inspection Findings. FAA, 19 October 2022. Piper Service Bulletin No. 1345, 27 March 2020. Piper Service Bulletin No. 1372, 3 April 2024. FAA Proposes Spar Inspections, Life Limits for Piper Singles. AOPA, 2 October 2024. EAA Comments on Proposed PA-28 and PA-32 Spar Airworthiness Directives. EAA, 2024. Piper Owner Society coverage of the 2019 proposed AD and industry objections. Piper Flyer Association, PA-28 wing spar history and the 1987 Marlin, Texas accident. Plane & Pilot coverage of the Embry-Riddle Arrow accident and NTSB findings. AVweb reporting on the 4 April 2018 Daytona Beach accident. Flying, NTSB final report coverage, September 2019. New Zealand CAA PA-28 Airworthiness Directive Schedule, amended 25 September 2025.