# Proposed AD FAA-2025-5394: Restricted Category Model CH-47D Helicopters

- Type: Proposed airworthiness directive (not in force)
- Status: Comment period closed
- Products: Billings Flying Service CH-47D
- Product type: Aircraft
- Action: Supplemental notice of proposed rulemaking (SNPRM).
- Published: July 8, 2026, 91 FR 42144
- Comments due: August 24, 2026
- Docket: FAA-2025-5394 (https://www.regulations.gov/docket/FAA-2025-5394, where comments are filed)
- Project: AD-2025-01194-R
- FR document: 2026-13781
- Official PDF: https://openairdocs.org/files/sha256/99/03/990377dcfe0a52c5d343e4da20f1344a9abc6d7cd979e94e3f87154818cf5b9c (from https://www.govinfo.gov/content/pkg/FR-2026-07-08/pdf/2026-13781.pdf)
- Federal Register: https://www.federalregister.gov/documents/2026/07/08/2026-13781/airworthiness-directives-restricted-category-model-ch-47d-helicopters
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/FR-ADNPRM-2026-13781-00000000000.0001
- Page: https://openairdocs.org/proposed/FAA-2025-5394

## Summary

The FAA is revising a notice of proposed rulemaking (NPRM) that would have applied to all restricted category Model CH-47D helicopters. This proposed action would revise the NPRM by expanding the required actions paragraph applicable to all right-hand (RH) forward transmission support beam fittings with any part number, narrowing the area of inspection, and increasing the reporting requirement compliance times. The FAA is proposing this airworthiness directive (AD) to address the unsafe condition on these products. Since these actions would impose an additional burden over those in the NPRM and to address some commenters' concerns, the agency is requesting comments on this SNPRM.

## Notices in this docket

- Dec 22, 2025: Notice of proposed rulemaking (NPRM). (first notice), FR document 2025-23613, comments due Feb 5, 2026 (https://www.federalregister.gov/documents/2025/12/22/2025-23613/airworthiness-directives-restricted-category-model-ch-47d-helicopters)
- Jul 8, 2026: Supplemental notice of proposed rulemaking (SNPRM)., FR document 2026-13781, comments due Aug 24, 2026 (https://www.federalregister.gov/documents/2026/07/08/2026-13781/airworthiness-directives-restricted-category-model-ch-47d-helicopters)

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