# Lycoming Mandatory Service Bulletin 667

## Copies (2)

Copies the FAA filed in AD dockets on regulations.gov, newest revision first. A newer revision may exist.

- Revision A ("Lycoming Mandatory Service Bulletin 667A"), 6 pages: PDF https://openairdocs.org/files/sha256/b5/8d/b58d94e6166ac36fd60c6914f15465d3555b9b1804ac525a032b89b906609a4f; text https://openairdocs.org/service-documents/lycoming/sb-667/file/b58d94e6166a.md. Rights: © Avco Corporation. Filed by the FAA in regulations.gov docket FAA-2026-13797; AD 2026-22-13 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.
- Revision A ("Lycoming_ SB_ 667A"), 6 pages: PDF https://openairdocs.org/files/sha256/25/d1/25d17fb7efb09bcc6365d5ec84500fee3bd1c2dfee6fd4a0b0c6595c98c08679; text https://openairdocs.org/service-documents/lycoming/sb-667/file/25d17fb7efb0.md. Rights: © Avco Corporation. Filed by the FAA in regulations.gov docket FAA-2026-8789; AD 2026-17-10 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.

## Details

- Manufacturer: [Lycoming](https://openairdocs.org/service-documents/lycoming.md)
- Type: Service bulletin (Mandatory Service Bulletin)
- Number: 667
- Latest revision known: 667A, dated March 12, 2026 (OpenAirDocs)
- Page: https://openairdocs.org/service-documents/lycoming/sb-667

## ADs that cite it (2) (OpenAirDocs)

Newest first, with the revision each names, as OpenAirDocs read it from the AD's text.

- [AD 2026-22-13](https://openairdocs.org/ad/2026-22-13.md), effective Nov 24, 2026: Revision A
- [AD 2026-17-10](https://openairdocs.org/ad/2026-17-10.md), effective Sep 14, 2026: Revision A

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