# Airworthiness Directives; Boeing Model 747-400 Series Airplanes
> **Rule** · Final rule. · Published 1998-11-25 · Effective 1998-12-30 · 63 FR 65054
## Document
- **Document number:** 98-31324
- **Category:** airworthiness
- **Manufacturer:** Boeing Model 747-400 Series
- **Type:** Rule
- **Action:** Final rule.
- **Citation:** 63 FR 65054
- **Publication date:** 1998-11-25
- **Effective date:** 1998-12-30
- **FAA docket:** Docket No. 97-NM-13-AD
## Abstract

This amendment adopts a new airworthiness directive (AD), applicable to certain Boeing Model 747-400 series airplanes, that requires replacing the cam assembly, cam bellcrank assembly, and thrust reverser control switch actuator on all four thrust levers with new components. This amendment is prompted by a report of an uncommanded automatic retraction of the leading edge flaps during takeoff. The actions specified by this AD are intended to prevent such uncommanded automatic retraction, which would seriously degrade liftoff and climb capabilities, and could result in near-stall conditions at a critical phase of the flight.

## Source
- [Federal Register document](https://www.federalregister.gov/documents/1998/11/25/98-31324/airworthiness-directives-boeing-model-747-400-series-airplanes)
---
*AI Analytics · CC0 1.0*