# Proposed AD 99-NE-51-AD: Honeywell International, Inc. (formerly AlliedSignal Inc., and Textron Lycoming) ALF502 and LF507 Series Turbofan Engines

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 2002-12-08
- Products: Honeywell International
- Product type: Engine
- Action: Notice of proposed rulemaking (NPRM).
- Published: August 23, 2001, 66 FR 44316
- Comments due: October 22, 2001
- Became: [AD 2002-12-08](https://openairdocs.org/ad/2002-12-08)
- Docket: 99-NE-51-AD
- FR document: 01-21222
- Official PDF: https://openairdocs.org/files/sha256/8c/63/8c634484d14a9fc81d137f776ad1cff9ff65577cbb8759f9cf186f863280add5 (from https://www.govinfo.gov/content/pkg/FR-2001-08-23/pdf/01-21222.pdf)
- Federal Register: https://www.federalregister.gov/documents/2001/08/23/01-21222/airworthiness-directives-honeywell-international-inc-formerly-alliedsignal-inc-and-textron-lycoming
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A7261FD9C6A98EE686256AB20046D4D7.0001
- Page: https://openairdocs.org/proposed/99-NE-51-AD

## Summary

This document proposes to adopt a new airworthiness directive (AD) that is applicable to Honeywell International, Inc. (formerly AlliedSignal Inc. and Textron Lycoming) ALF502 and LF507 series turbofan engines. This proposal would require removing from service certain gas producer turbine (GPT) components prior to reaching new, lower cyclic life limits using drawdown plans, and replacing with serviceable parts. This proposal is prompted by continuous analysis of field-returned hardware indicating smaller service life margins than originally expected. The actions specified by the proposed AD are intended to prevent GPT component failure, which could result in an uncontained engine failure and damage to the airplane.

## Notices in this docket

- Aug 23, 2001: Notice of proposed rulemaking (NPRM). (first notice), FR document 01-21222, comments due Oct 22, 2001 (https://www.federalregister.gov/documents/2001/08/23/01-21222/airworthiness-directives-honeywell-international-inc-formerly-alliedsignal-inc-and-textron-lycoming)

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