# Proposed AD 99-NE-21-AD: Hartzell Propeller Inc. ()HC-()()Y()-() Series Propellers

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2001-07-03
- Action: Notice of proposed rulemaking (NPRM).
- Published: September 20, 1999, 64 FR 50781
- Comments due: November 19, 1999
- Became: [AD 2001-07-03](https://openairdocs.org/ad/2001-07-03)
- Docket: 99-NE-21-AD
- FR document: 99-24461
- Official PDF: https://openairdocs.org/files/sha256/cc/af/ccafe6be3ffcaa4c0897212a521f2c3d38437dbca1a80b5f5f54370790e273b0 (from https://www.govinfo.gov/content/pkg/FR-1999-09-20/pdf/99-24461.pdf)
- Federal Register: https://www.federalregister.gov/documents/1999/09/20/99-24461/airworthiness-directives-hartzell-propeller-inc-hc-y--series-propellers
- Page: https://openairdocs.org/proposed/99-NE-21-AD

## Summary

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Hartzell Propeller Inc. ()HC-()()Y()-() series propellers, identified by hub serial numbers, that were returned to service by Brothers Aero Services Company, Inc. (BASCO). This proposal would require maintenance actions amounting to an overhaul of affected propellers. This proposal is prompted by reports of propellers returned to service by BASCO as overhauled that had numerous unsafe conditions after being returned to service by BASCO. The actions specified by the proposed AD are intended to prevent propeller failure from the conditions present after being returned to service by BASCO, and possible airplane loss of control.

## Notices in this docket

- Sep 20, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-24461, comments due Nov 19, 1999 (https://www.federalregister.gov/documents/1999/09/20/99-24461/airworthiness-directives-hartzell-propeller-inc-hc-y--series-propellers)

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