AD/B747/84 Amdt 1 - Trailing Edge Flap Tracks Forward End Clevis Lug

Overview

The Civil Aviation Safety Regulations 1998 (CASR 1998) were enacted to establish and maintain high standards of safety in civil aviation. They provide the regulatory framework for ensuring that aircraft and aeronautical products meet the necessary safety standards to operate in Australian airspace. One of the key mechanisms through which these regulations are enforced is the issuance of Airworthiness Directives (ADs). These directives are issued by the Civil Aviation Safety Authority (CASA) to address specific safety concerns identified in aircraft or aeronautical products. In the case of the Boeing 747 series aeroplanes, AD/B747/84 Amendment 1 was issued to address the risk of cracking in the forward end clevis lugs of the flap tracks, which could compromise the structural integrity of the flaps and subsequently the controllability of the aircraft. This amendment was necessitated by a corresponding Federal Aviation Administration (FAA) directive, which expanded the scope of required inspections and mandated the replacement of affected components. The objective of this directive is to ensure that the specified maintenance actions are undertaken to mitigate the identified safety risks, thereby maintaining the airworthiness of the aircraft.

Scope and Application

The Civil Aviation Safety Regulations 1998, specifically Part 39 - 105, sets forth detailed regulations concerning airworthiness directives under the authority of the Civil Aviation Safety Authority (CASA). These regulations apply to certain aircraft models, in this case the Boeing 747 Series Aeroplanes, as listed in the applicability section of the Airworthiness Directive. The directive mandates specific actions to be taken by aircraft operators to address identified safety concerns, such as cracking of the forward end clevis lugs of the flap tracks, in accordance with the technical requirements set out by the Federal Aviation Administration (FAA). Compliance with these directives is mandatory for all relevant aircraft, and failure to adhere to the specified timelines and actions can result in significant safety risks, including reduced structural capability and controllability of the aircraft. The scope of this directive is geographically limited to the Commonwealth of Australia, but it aligns closely with international standards set by the FAA. Exemptions or exclusions from these requirements are not specified in the text, implying that all affected aircraft must comply. The application of these regulations can be extended or modified through subordinate instruments issued by CASA.

Key Provisions

The Civil Aviation Safety Regulations 1998, specifically under Part 39, Section 105, establish the framework for issuing Airworthiness Directives (AD) by the Civil Aviation Safety Authority (CASA) (CASR 1998, Part 39, Section 105). The AD mandates corrective actions to be undertaken in relation to certain aircraft or aeronautical products to address identified safety issues. For instance, in this case, AD/B747/84 Amendment 1 addresses issues with the trailing edge flap tracks forward end clevis lug on Boeing 747 Series Aeroplanes, as outlined in the requirement section (CASR 1998, Part 39, Section 105(a)-(c)). Under this AD, specific obligations are imposed on the operators of Boeing 747 series aircraft, as listed in Boeing Service Bulletin 747-57-2307 Revision 1 dated 17 January 2002. These obligations include conducting inspections for cracking of the forward end clevis lugs of the flap track, replacing the flap track if necessary, and optionally modifying the clevis lugs in accordance with the technical requirements of FAA AD 2003-14-15 Amdt 39-13234. Furthermore, the AD requires repetitive inspections to detect any rotation or migration of the bushings or further cracking of the lugs, as specified in the requirement document, with an effective date of 30 October 2003. Compliance with these requirements is critical to ensuring the continued airworthiness and safety of the affected aircraft. Failure to adhere to the requirements set out in the Airworthiness Directive may result in serious safety risks, including reduced structural capability of the flap and reduced controllability of the aircraft. The AD is issued in response to the Federal Aviation Administration's (FAA) requirement for inspections and corrective actions to address potential cracking and fracture of the forward end clevis of the flap track. The CASA delegate, David Villiers, has revoked the previous AD/B747/84 and issued this new AD, effective as of 30 October 2003, to address the identified safety concerns. Non-compliance with the AD may result in enforcement actions, including potential civil or criminal penalties, depending on the severity of the breach and the impact on aviation safety. The AD is published in the Commonwealth of Australia Gazette on 8 October 2003, providing official notification to relevant stakeholders, including aircraft operators, maintenance organisations, and other interested parties. This notification ensures that all parties are aware of the new safety requirements and can take appropriate action to comply with the AD and maintain the airworthiness of their aircraft. The AD remains in effect until further notice or until it is amended or revoked by the CASA delegate.