# 2026-00409: Boeing 737 Wings Get Crack Checks Ordered by FAA

2026-00409, Airworthiness Directives; The Boeing Company Airplanes, is a Federal Register proposed rule from Transportation Department, Federal Aviation Administration published 2026-01-12, effective The FAA must receive comments on this proposed AD by February 26, 2026. (as of 2026-06-11).

- Canonical: https://policyrisk.com/federal-register/2026-00409
- As of: 2026-06-11
- Plain-text twin of the page above; the HTML and this file carry the same facts.

## Facts
- Document number: 2026-00409
- Title: Airworthiness Directives; The Boeing Company Airplanes
- Type: Proposed Rule
- Agencies: Transportation Department; Federal Aviation Administration
- Citation: 91 FR 1104
- Published: 2026-01-12
- Effective: The FAA must receive comments on this proposed AD by February 26, 2026.
- Comments close: not stated
- Significant: no
- Touches household money: no
- Regulation identifier numbers: 2120-AA64
- Last updated: 2026-06-11

## In one line

Boeing 737 Wings Get Crack Checks Ordered by FAA

## Summary

The FAA wants to make sure Boeing 737 planes stay safe by checking for cracks on the lower wing skin. Owners of 737-700, -700C, -800, -900, and -900ER models will need to inspect their wings and fix any problems found. Comments on this plan are open until February 26, 2026, and these inspections could mean some extra maintenance costs but keep flights safe and sound.

## Abstract

The FAA proposes to adopt a new airworthiness directive (AD) for all The Boeing Company Model 737-700, -700C, -800, -900, and -900ER series airplanes. This proposed AD was prompted by reports of cracks in the outward lower wing skin at the outboard end of a certain stringer. This proposed AD would require an inspection of the outboard lower wing skin on the left and right wing for any repair, repetitive inspections for cracking and applicable on-condition actions. The FAA is proposing this AD to address the unsafe condition on these products.

## Effects PRIA read

- Mandatory wing inspections for certain 737s: cost, medium. If you operate Boeing Model 737-700, -700C, -800, -900, or -900ER airplanes, the FAA proposes required inspections of the outboard lower wing skin at stringers S-9 and S-10 on both left and right wings, repetitive HFEC inspections, and required on‑condition repairs. The FAA estimates this proposed…
- Per-inspection labor cost and U.S. total: cost, low. The FAA estimates a general visual inspection (left and right wing) takes 2 work-hours at $85/hour = $170 per airplane, and an HFEC inspection takes 2 work-hours at $85/hour = $170 per inspection cycle. The FAA estimates the cost to U.S. operators for each inspection type across the affected fleet…
- Estimated on-condition repair cost per airplane: cost, high. For any crack outside the skin cutout boundary found by the inspections, the FAA estimates repairs would require about 54 work‑hours (54 x $85 = $4,590) plus parts costing up to $11,180, for a total up to $15,770 per product. The FAA says it cannot determine how many airplanes will need those on-co…
- Compliance timing and inspection intervals: cost, medium. The proposed rule sets the earliest initial compliance time in the Aviation Partners Boeing bulletin as before 20,000 flight cycles or before 40,000 flight hours, whichever comes first, and specifies that repetitive inspection intervals vary by configuration with the earliest repetitive interval be…

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## Sources
- [2026-00409 on federalregister.gov](https://www.federalregister.gov/documents/2026/01/12/2026-00409/airworthiness-directives-the-boeing-company-airplanes)
- [2026-00409 as published (PDF)](https://www.govinfo.gov/content/pkg/FR-2026-01-12/pdf/2026-00409.pdf)

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- [All Federal Register documents](https://policyrisk.com/federal-register)

Source: PRIA, https://policyrisk.com/federal-register/2026-00409 (as of 2026-06-11).