# Proposed AD FAA-2013-0770: Eurocopter France (Eurocopter) Helicopters

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2014-04-12
- Products: Eurocopter France
- Product type: Aircraft
- Action: Notice of proposed rulemaking (NPRM).
- Published: September 6, 2013, 78 FR 54792
- Comments due: November 5, 2013
- Became: [AD 2014-04-12](https://openairdocs.org/ad/2014-04-12)
- Docket: FAA-2013-0770 (https://www.regulations.gov/docket/FAA-2013-0770, where comments are filed)
- Project: 2011-SW-057-AD
- FR document: 2013-21724
- Official PDF: https://openairdocs.org/files/sha256/55/f9/55f936b8c067ba30266421e56803b19b571079fef726874ee5f293e1ebc29c4a (from https://www.govinfo.gov/content/pkg/FR-2013-09-06/pdf/2013-21724.pdf)
- Federal Register: https://www.federalregister.gov/documents/2013/09/06/2013-21724/airworthiness-directives-eurocopter-france-eurocopter-helicopters
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/66E766757C35670E86257BDE004815D6.0001
- Page: https://openairdocs.org/proposed/FAA-2013-0770

## Summary

We propose to adopt a new airworthiness directive (AD) for certain Eurocopter Model EC225 LP helicopters. This proposed AD would add a new operating limitation that would require increasing the minimum density altitude flight limitation for helicopters without certain Eurocopter modifications installed. This proposed AD is prompted by a report that flights below a certain density altitude create oscillations in the main rotor which can transfer dynamic loads to the structure, the main gearbox (MGB), and the main servo-control inputs, which could result in subsequent loss of control of the helicopter.

## Notices in this docket

- Sep 6, 2013: Notice of proposed rulemaking (NPRM). (first notice), FR document 2013-21724, comments due Nov 5, 2013 (https://www.federalregister.gov/documents/2013/09/06/2013-21724/airworthiness-directives-eurocopter-france-eurocopter-helicopters)

---
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.