# 2026-16504: Boeing Wings Get Eddy Current Checkup Mandate

2026-16504, Airworthiness Directives; The Boeing Company Airplanes, is a Federal Register rule from Transportation Department, Federal Aviation Administration published 2026-08-13, effective 2026-09-17; PRIA reads it as touching household money (as of 2026-08-20).

- Canonical: https://policyrisk.com/federal-register/2026-16504
- As of: 2026-08-20
- Plain-text twin of the page above; the HTML and this file carry the same facts.

## Facts
- Document number: 2026-16504
- Title: Airworthiness Directives; The Boeing Company Airplanes
- Type: Rule
- Agencies: Transportation Department; Federal Aviation Administration
- Citation: 91 FR 52223
- Published: 2026-08-13
- Effective: 2026-09-17
- Comments close: not stated
- Significant: no
- Touches household money: yes
- Regulation identifier numbers: 2120-AA64
- Last updated: 2026-08-20

## In one line

Boeing Wings Get Eddy Current Checkup Mandate

## Summary

The FAA is superseding Airworthiness Directive (AD) 2018-11- 14, which applied to certain The Boeing Company Model 767-300 and -300F series airplanes with certain winglets installed. AD 2018-11-14 required high frequency eddy current (HFEC) inspections for cracking of the lower outboard wing skin and repair or modification if necessary. AD 2018-11-14 also required one of three follow-on actions: Repeating the HFEC inspections; modifying certain internal stringers and oversizing and plugging the existing fastener holes of the lower wing; or modifying the external doubler/tripler and doing repetitive post- modification inspections. This AD was prompted by reports of fatigue cracking in the lower outboard wing skin at the inboard fastener of stringer L-9.5, and the lower outboard wing skin of stringer L-6.5, on airplanes with winglets installed per Supplemental Type Certificate (STC) ST01920SE. This AD was also prompted by a determination that, for certain airplanes, the area of the lower wing skin in the vicinity of the critical inboard end fasteners of installed repair doublers must be inspected. This AD continues to require the actions in AD 2018-11-14, adds to the applicability airplanes that have had STC ST01920SE installed and the STC winglets removed, and, for certain airplanes, requires repetitive internal and external HFEC inspections of the lower outboard wing skin common to the external doubler repair at stringer L- 9.5 and repair if necessary. The FAA is issuing this AD to address the unsafe condition on these products.

## Effects PRIA read

- Mandatory HFEC Inspections for Affected 767s: cost, high. If you operate a Boeing Model 767-300 or -300F provisioned for blended winglets modified in accordance with STC ST01920SE (with or without winglets installed), you must perform high frequency eddy current (HFEC) inspections for cracking of the lower outboard wing skin and do required repairs or mod…
- Planes With Removed STC Winglets Now Covered: cost, medium. The AD expands applicability to Model 767-300 and -300F airplanes provisioned for blended winglets modified in accordance with STC ST01920SE even if the STC winglets have been removed. If your airplane previously had STC ST01920SE installed but the winglets were later removed, the inspection and re…
- Required Timing and 3,000-Cycle Grace: cost, medium. This AD is effective September 17, 2026. For Group 3 airplanes, the AD requires initial internal and external HFEC inspections at the times in APB Service Bulletin AP767-57-010, Revision 14, dated November 17, 2025, or within 3,000 flight cycles after the effective date of this AD, whichever occurs…
- FAA Cost Estimates Per Airplane: cost, high. The FAA estimates the AD affects 195 U.S.-registered airplanes. Estimated direct costs include: HFEC inspections at 6 work-hours × $85 = $510 per inspection cycle; internal and external HFEC inspections (Group 3) at 3 work-hours × $85 = $255 per inspection cycle; repair/modification estimated at 26…
- Operators Can Seek Alternative Compliance: benefit, low. The AD states anyone may request an alternative method of compliance (AMOC) under paragraph (q) of the AD; alternative inspection methods may be allowed if they provide an acceptable level of safety. The FAA also noted operators remain free to engage private businesses or technologies for complianc…

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## Sources
- [2026-16504 on federalregister.gov](https://www.federalregister.gov/documents/2026/08/13/2026-16504/airworthiness-directives-the-boeing-company-airplanes)
- [2026-16504 as published (PDF)](https://www.govinfo.gov/content/pkg/FR-2026-08-13/pdf/2026-16504.pdf)

## Related
- [Previous: 2026-16503, Empowering Broadband Consumers Through Transparency](https://policyrisk.com/federal-register/2026-16503)
- [Next: 2026-16505, Airworthiness Directives; Airbus Helicopters](https://policyrisk.com/federal-register/2026-16505)
- [All Federal Register documents](https://policyrisk.com/federal-register)

Source: PRIA, https://policyrisk.com/federal-register/2026-16504 (as of 2026-08-20).