# Airworthiness Directives; Boeing Model 747-400 and -400F Series Airplanes Powered by Rolls-Royce RB211 Series Engines
> **Rule** · Final rule; request for comments. · Published 2009-06-30 · Effective 2009-07-06 · 74 FR 31169
## Document
- **Document number:** E9-15255
- **Category:** airworthiness
- **Manufacturer:** Boeing Model 747-400 and -400F Series
- **Type:** Rule
- **Action:** Final rule; request for comments.
- **Citation:** 74 FR 31169
- **Publication date:** 2009-06-30
- **Effective date:** 2009-07-06
- **FAA docket:** Docket No. FAA-2009-0556
## Abstract

We are adopting a new airworthiness directive (AD) for certain Boeing Model 747-400 and -400F series airplanes. This AD requires modifying certain thrust reverser control system wiring to the flap control unit (FCU). This AD results from a report of automatic retraction of the leading edge flaps during takeoff due to indications transmitted to the FCU from the thrust reverser control system. We are issuing this AD to prevent automatic retraction of the leading edge flaps during takeoff, which could result in reduced climb performance and consequent collision with terrain and obstacles or forced landing of the airplane.

## Source
- [Federal Register document](https://www.federalregister.gov/documents/2009/06/30/E9-15255/airworthiness-directives-boeing-model-747-400-and--400f-series-airplanes-powered-by-rolls-royce)
---
*AI Analytics · CC0 1.0*