# Leonardo Alert Service Bulletin 139-633

Copy: Revision A ("Leonardo Helicopters ASB No_ 139-633 Rev A"), 20 pages: PDF https://openairdocs.org/files/sha256/a3/dc/a3dc62c5b92821b1aa7e5a83679d6f130889d38d53b17a3ff0b6b3a2c4c74c1a; text https://openairdocs.org/service-documents/leonardo/sb-139-633/file/a3dc62c5b928.md. Rights: © Leonardo S.p.A. Filed by the FAA in regulations.gov docket FAA-2021-0025; AD 2021-04-01 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication.

## Details

- Manufacturer: [Leonardo](https://openairdocs.org/service-documents/leonardo.md)
- Type: Service bulletin (Alert Service Bulletin)
- Number: 139-633
- Latest revision known: 139-633, Revision A, dated September 2, 2020 (OpenAirDocs)
- Page: https://openairdocs.org/service-documents/leonardo/sb-139-633

## ADs that cite it (1) (OpenAirDocs)

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

- [AD 2021-04-01](https://openairdocs.org/ad/2021-04-01.md), effective Mar 26, 2021: Revision A

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