# Leonardo Alert Service Bulletin 139-452

## Copies (3)

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

- Revision B ("Finmeccanica Helicopter Division BT 139-452"), 19 pages: PDF https://openairdocs.org/files/sha256/49/b5/49b5dc1bf84abe7ac56c3374452ca95c0f1a3f70c793ca40d3dc3172e2e860f5; text https://openairdocs.org/service-documents/leonardo/sb-139-452/file/49b5dc1bf84a.md. Rights: © Leonardo S.p.A. Filed by the FAA in regulations.gov docket FAA-2020-0283, the docket of AD 2021-23-22. Not covered by OpenAirDocs’ CC0 dedication.
- Revision B ("Leonardo Helicopters ASB No. 139-452 Rev B"), 12 pages: PDF https://openairdocs.org/files/sha256/f9/32/f932c5c19ce7fcf3a4ecd80e495e35ddd155324120cb4e3cfec804a1160f8006; text https://openairdocs.org/service-documents/leonardo/sb-139-452/file/f932c5c19ce7.md. Rights: © Leonardo S.p.A. Filed by the FAA in regulations.gov docket FAA-2020-0283, the docket of AD 2021-23-22. Not covered by OpenAirDocs’ CC0 dedication.
- Revision B ("Leonardo Helicopters Mandatory BT No. 139-452 Rev A"), 21 pages: PDF https://openairdocs.org/files/sha256/18/8d/188d733203482df6974c13db54445408bb3f958aa8eaa261435a6740019481b1; text https://openairdocs.org/service-documents/leonardo/sb-139-452/file/188d73320348.md. Rights: © Leonardo S.p.A. Filed by the FAA in regulations.gov docket FAA-2020-0283, the docket of AD 2021-23-22. Not covered by OpenAirDocs’ CC0 dedication.

## Details

- Manufacturer: [Leonardo](https://openairdocs.org/service-documents/leonardo.md)
- Type: Service bulletin (Alert Service Bulletin)
- Number: 139-452
- Latest revision known: 139-452, Revision B, dated April 10, 2018 (OpenAirDocs)
- Page: https://openairdocs.org/service-documents/leonardo/sb-139-452

Also cited in [1 proposed AD](https://openairdocs.org/service-documents/leonardo/sb-139-452/proposed.md).

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