# Proposed AD 99-NM-101-AD: Boeing Model 757 Series Airplanes

- Type: Proposed airworthiness directive (not in force)
- Status: Became AD 99-23-21
- Action: Notice of proposed rulemaking (NPRM).
- Published: August 23, 1999, 64 FR 45927
- Comments due: October 7, 1999
- Became: [AD 99-23-21](https://openairdocs.org/ad/99-23-21)
- Docket: 99-NM-101-AD
- FR document: 99-21846
- Official PDF: https://openairdocs.org/files/sha256/d8/21/d821c5c57231d73371bfd2a0458f1e187a6373d0c6357b0eda3555f350e95569 (from https://www.govinfo.gov/content/pkg/FR-1999-08-23/pdf/99-21846.pdf)
- Federal Register: https://www.federalregister.gov/documents/1999/08/23/99-21846/airworthiness-directives-boeing-model-757-series-airplanes
- Page: https://openairdocs.org/proposed/99-NM-101-AD

## Summary

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 757 series airplanes. This proposal would require a modification of the reverse thrust lever assemblies and replacement of the spring bumper assemblies of the thrust reverser sleeves with new assemblies. This proposal is prompted by an FAA review of the thrust reverser system on all transport category airplanes including the Boeing Model 757 series airplane. The actions specified by the proposed AD are intended to prevent operation with an energized sync lock or malfunctioning sleeve locking devices, which could result in the deployment of a thrust reverser in flight and subsequent reduced controllability of the airplane.

## Notices in this docket

- Aug 23, 1999: Notice of proposed rulemaking (NPRM). (first notice), FR document 99-21846, comments due Oct 7, 1999 (https://www.federalregister.gov/documents/1999/08/23/99-21846/airworthiness-directives-boeing-model-757-series-airplanes)

---
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.