# Proposed AD 98-SW-62-AD: Bell Helicopter Textron Canada (BHTC) Model 206L-4 Helicopters

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 99-13-10
- Action: Notice of proposed rulemaking (NPRM).
- Published: March 9, 1999, 64 FR 11401
- Comments due: May 10, 1999
- Became: [AD 99-13-10](https://openairdocs.org/ad/99-13-10)
- Docket: 98-SW-62-AD
- FR document: 99-5723
- Official PDF: https://openairdocs.org/files/sha256/b2/51/b2513e0cc09002ca28254c0ba370a4b051035608800797e54a55b60cc2f1e879 (from https://www.govinfo.gov/content/pkg/FR-1999-03-09/pdf/99-5723.pdf)
- Federal Register: https://www.federalregister.gov/documents/1999/03/09/99-5723/airworthiness-directives-bell-helicopter-textron-canada-bhtc-model-206l-4-helicopters
- Page: https://openairdocs.org/proposed/98-SW-62-AD

## Summary

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to BHTC Model 206L-4 helicopters. This proposal would require replacing certain hydraulic relief valves (valves) with airworthy valves. This proposal is prompted by a pilot's report of intermittent hydraulic pressure in the flight controls that was caused by a defective hydraulic relief valve. The actions specified by the proposed AD are intended to prevent intermittent hydraulic pressure to the flight controls and subsequent loss of control of the helicopter.

## Notices in this docket

- Mar 9, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-5723, comments due May 10, 1999 (https://www.federalregister.gov/documents/1999/03/09/99-5723/airworthiness-directives-bell-helicopter-textron-canada-bhtc-model-206l-4-helicopters)

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