# Proposed AD FAA-2010-0610: Eurocopter France Model EC 155B, EC155B1, SA-360C, SA-365C, SA-365C1, SA-365C2, SA-365N, SA-365N1, AS- 365N2, AS 365 N3, and SA-366G1 Helicopters

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2010-20-20
- Products: Eurocopter France
- Product type: Aircraft
- Action: Notice of proposed rulemaking (NPRM).
- Published: June 28, 2010, 75 FR 36581
- Comments due: August 27, 2010
- Became: [AD 2010-20-20](https://openairdocs.org/ad/2010-20-20)
- Docket: FAA-2010-0610 (https://www.regulations.gov/docket/FAA-2010-0610, where comments are filed)
- Project: 2009-SW-47-AD
- FR document: 2010-15370
- Official PDF: https://openairdocs.org/files/sha256/31/f8/31f87bd8ef3275a01532e52413891555a08ad1e0f580662ee9369ea08bd2686d (from https://www.govinfo.gov/content/pkg/FR-2010-06-28/pdf/2010-15370.pdf)
- Federal Register: https://www.federalregister.gov/documents/2010/06/28/2010-15370/airworthiness-directives-eurocopter-france-model-ec-155b-ec155b1-sa-360c-sa-365c-sa-365c1-sa-365c2
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/82CCD608DEDE55EC86257750004AFA2E.0001
- Page: https://openairdocs.org/proposed/FAA-2010-0610

## Summary

This document proposes superseding an existing airworthiness directive (AD) for the specified Eurocopter France (Eurocopter) helicopters. That AD requires repetitively inspecting the main gearbox (MGB) planet gear carrier for a crack and replacing any MGB that has a cracked planet gear carrier before further flight. This action would require the same inspections required by the existing AD but would shorten the initial inspection interval. This proposal is prompted by the discovery of another crack in a MGB planet gear carrier and additional analysis that indicates that the initial inspection interval must be shortened. The actions specified by the proposed AD are intended to detect a crack in the web of the planet gear carrier, which could lead to a MGB seizure and subsequent loss of control of the helicopter.

## Notices in this docket

- Jun 28, 2010: Notice of proposed rulemaking (NPRM). (first notice), FR document 2010-15370, comments due Aug 27, 2010 (https://www.federalregister.gov/documents/2010/06/28/2010-15370/airworthiness-directives-eurocopter-france-model-ec-155b-ec155b1-sa-360c-sa-365c-sa-365c1-sa-365c2)

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.