# Proposed AD FAA-2013-0500: Bell Helicopter Textron, Inc. (Bell), Model Helicopters

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2013-20-18
- Products: Bell Helicopter Textron
- Product type: Aircraft
- Action: Notice of proposed rulemaking (NPRM).
- Published: June 11, 2013, 78 FR 34958
- Comments due: August 12, 2013
- Became: [AD 2013-20-18](https://openairdocs.org/ad/2013-20-18)
- Docket: FAA-2013-0500 (https://www.regulations.gov/docket/FAA-2013-0500, where comments are filed)
- Project: 2012-SW-45-AD
- FR document: 2013-13797
- Official PDF: https://openairdocs.org/files/sha256/f0/00/f0009aaf0a3843484bb181a0e02ffd23a0d90030aa60d0f25cc0d938bee2c945 (from https://www.govinfo.gov/content/pkg/FR-2013-06-11/pdf/2013-13797.pdf)
- Federal Register: https://www.federalregister.gov/documents/2013/06/11/2013-13797/airworthiness-directives-bell-helicopter-textron-inc-bell-model-helicopters
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/139B692EEE0556FC86257B870044AD52.0001
- Page: https://openairdocs.org/proposed/FAA-2013-0500

## Summary

This document proposes to supersede an existing airworthiness directive (AD) for the Bell Model 412, 412CF, and 412EP helicopters. The AD currently requires reidentifying each affected part-numbered main rotor yoke (yoke) on its data plate, reducing the retirement life of the reidentified yoke, and revising the Airworthiness Limitations section of the maintenance manual or the Instructions for Continued Airworthiness (ICAs) accordingly. Since we issued the AD, we have discovered that the affected yokes do not have a data plate, making compliance with the part-marking requirements of the existing AD impossible. This proposed AD would retain the current requirements with the exception of the P/N marking location. The actions specified in this AD are intended to prevent fatigue cracking of a yoke, failure of the yoke, and subsequent loss of control of the helicopter.

## Notices in this docket

- Jun 11, 2013: Notice of proposed rulemaking (NPRM). (first notice), FR document 2013-13797, comments due Aug 12, 2013 (https://www.federalregister.gov/documents/2013/06/11/2013-13797/airworthiness-directives-bell-helicopter-textron-inc-bell-model-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.