Commonwealth legislation

AD/B747/268 - Trailing Edge Flap Transmission Torque Brake

In ForceCTH

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

3/10 complexity

This Airworthiness Directive orders operators of Boeing 747 aeroplanes (line numbers 0001–1207, excluding 1174, and excluding 747SP) to remove, rework or replace certain trailing-edge flap transmission torque brakes because they may not lock at the intended torque and could cause flap asymmetry. It adopts the FAA’s technical remedy and immediately prohibits installing the listed torque-brake assemblies at positions 2 or 7. It matters because it forces specific maintenance and parts controls to address a mechanical safety risk.

JSON API

Deep dive

Want the full deep dive?

Zoe can write the in-depth analysis on top of the summary above: how it works, who it affects and what each part actually does.

Current sections

Direct links to the current provisions in AD/B747/268 - Trailing Edge Flap Transmission Torque Brake.

AIRWORTHINESS DIRECTIVE

View image in the official source

View image in the official source
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Boeing 747 Series Aeroplanes

AD/B747/268 Trailing Edge Flap Transmiss

AD/B747/268 Trailing Edge Flap Transmission Torque Brake 5/2002

Applicability: Model 747 series aeroplanes line numbers 0001 to 1207, excluding line number 1174 and Model 747SP series aeroplanes.

Requirement: 1. Action in accordance with the technical requirements of CORRECTION FAA AD 2001-23-13 Amendment 39-12512 issued in Renton, Washington, on 7 February 2002.

No person shall install on any aircraft any transmission or torque brake assembly of the trailing edge flaps at positions 2 or 7 as identified in the “Existing Part Number” column of paragraph 2.E of Boeing Service Bulletin 747-27-2374 dated 18 November, 1999.

Compliance: Requirement 1: Within 13 months or 5,400 flight hours after the effective date of this Airworthiness Directive, whichever occurs later.

Requirement 2: From the date when this Directive becomes effective. This Airworthiness Directive becomes effective on 16 May 2002.

Background: The manufacturer raised a Service Bulletin after it was found that the trailing edge flap transmission torque brake (Belleville spring design) does not lockout at the intended torque levels. If a flap jam occurred, and the torque brake failed to limit the torque of the transmission, the resultant force may cause the transmission mounts to fail. This Airworthiness Directive has therefore been raised to remove, rework or replace such torque brakes to prevent damage to the flap system, adjacent systems, or structural components; or excessive skew of the trailing edge flap, that could result in flap asymmetry and consequent reduced controllability of the aeroplane.

Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.

Eugene Paul Holzapfel

Delegate of the Civil Aviation Safety Authority 27 March 2002

View image in the official source

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

AIRWORTHINESS DIRECTIVE AIRWORTHINESS DIRECTIVE

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Boeing 747 Series Aeroplanes

AD/B747/268 Trailing Edge Flap Transmiss AD/B747/268 Trailing Edge Flap Transmission Torque Brake 5/2002

AD/B747/268 Trailing Edge Flap Transmission Torque Brake 5/2002

Applicability: Model 747 series aeroplanes line numbers 0001 to 1207, excluding line number 1174 and Model 747SP series aeroplanes.

Requirement: 1. Action in accordance with the technical requirements of CORRECTION FAA AD 2001-23-13 Amendment 39-12512 issued in Renton, Washington, on 7 February 2002.

No person shall install on any aircraft any transmission or torque brake assembly of the trailing edge flaps at positions 2 or 7 as identified in the “Existing Part Number” column of paragraph 2.E of Boeing Service Bulletin 747-27-2374 dated 18 November, 1999.

Compliance: Requirement 1: Within 13 months or 5,400 flight hours after the effective date of this Airworthiness Directive, whichever occurs later.

Requirement 2: From the date when this Directive becomes effective. This Airworthiness Directive becomes effective on 16 May 2002.

Eugene Paul Holzapfel