COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Boeing 747 Series Aeroplanes
AD/B747/145
Amdt 1
Outboard Engine Strut Spring Beam 1/99
Applicability: Model 747 series aircraft, line numbers 202 through 396, equipped with Pratt & Whitney Model JT9D-70 engines.
Requirement: Action in accordance with the technical requirements of FAA AD 98-21-17 Amdt 39- 10826.
Note: Boeing Service Bulletins 747-54A2171 and 747-54-2177 refer.
Compliance: As specified in the Requirement Document with a revised effective date of 28 January 1999.
This Amendment becomes effective on 28 January 1999.
Background: A failure of an outboard spring beam on a number 4 engine strut was reported. The failure was due to a material problem in the titanium spring beam which is only fitted to B747 aircraft with JT9D-70 engines. Continued operation with a damaged spring beam could result in loss of an engine.
Amendment 1 is issued in response to a new FAA AD which was prompted by the development of an improved process for manufacturing titanium spring beams that will eliminate the embedded porosity flaws in the existing spring beams, from which fatigue cracking can originate.
The original issue of this Airworthiness Directive became effective on 25 June 1995.
Overview
The Civil Aviation Regulations 1998, as amended by F2006B03046, address issues related to the airworthiness of Boeing 747 series aircraft equipped with Pratt & Whitney Model JT9D-70 engines, specifically targeting a problem with the outboard engine strut spring beam. This legislative instrument was introduced to ensure the safety and reliability of these aircraft by mandating compliance with the technical requirements outlined in FAA AD 98-21-17 Amdt 39-10826, which was developed in response to a material defect in the titanium spring beam. The policy objective is to prevent potential failures that could result in the loss of an engine, thereby maintaining the safety standards set by the Civil Aviation Safety Authority. This amendment was necessitated by the need to address a reported failure of an outboard spring beam on a number 4 engine strut, which was linked to a material problem in the titanium component. The amendment became effective on 28 January 1999, ensuring that all affected aircraft were retrofitted with improved components as per the new manufacturing process designed to eliminate porosity flaws that could lead to fatigue cracking.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandates airworthiness directives that apply to the operation and maintenance of aircraft within Australia. This legislation targets the Boeing 747 series aeroplanes, particularly those with line numbers 202 through 396, which are equipped with Pratt & Whitney Model JT9D-70 engines. The Act requires compliance with the technical specifications outlined in FAA AD 98-21-17 Amdt 39-10826, as referenced in Boeing Service Bulletins 747-54A2171 and 747-54-2177. These technical requirements are intended to address and rectify the issue of outboard engine strut spring beam failures, which were caused by material problems in the titanium spring beams. Non-compliance with these directives could result in significant safety risks, including the potential loss of an engine. The regulations are designed to ensure that these aircraft maintain the necessary safety standards for operation within Australia and are subject to the oversight of the Civil Aviation Safety Authority.
Key Provisions
The Civil Aviation Regulations 1998, particularly PART 39 - 105, establish the framework for ensuring the airworthiness of aircraft, with a specific focus on the Boeing 747 series aeroplanes in this instance. Section AD/B747/145 Amendment 1 pertains to the outboard engine strut spring beam and applies to Model 747 series aircraft with line numbers ranging from 202 through 396, specifically those equipped with Pratt & Whitney Model JT9D-70 engines. This amendment mandates adherence to the technical requirements outlined in FAA AD 98-21-17 Amendment 39-10826, which addresses a previously reported failure of an outboard spring beam on a number 4 engine strut. The failure was attributed to a material defect in the titanium spring beam, a component unique to Boeing 747 aircraft with JT9D-70 engines. The directive requires compliance with specified technical requirements to prevent potential engine loss due to continued operation with a compromised spring beam.
Operators and owners of the affected Boeing 747 aircraft must ensure that the specified action is taken in accordance with the FAA AD 98-21-17 Amendment 39-10826, as referenced in the Requirement Document. This includes following the revised effective date of 28 January 1999, which aligns with the effective date of the Amendment. Compliance involves either implementing the required modifications or replacing the outboard engine strut spring beam to address the material defect identified. Failure to comply with this directive could result in non-compliance with the Civil Aviation Regulations, potentially impacting the aircraft's airworthiness certification and authorisation for flight.
Failure to adhere to the requirements set forth in the Civil Aviation Regulations 1998, PART 39 - 105, specifically regarding the outboard engine strut spring beam, may result in serious consequences. The primary regulatory body, the Civil Aviation Safety Authority (CASA), can impose penalties on operators and owners who fail to comply with Airworthiness Directives. Such penalties may include fines, suspension or revocation of the aircraft's certificate of airworthiness, and restrictions on the operation of the aircraft. Furthermore, non-compliance could lead to civil or criminal liabilities under other sections of the Civil Aviation Act 1988, which may include imprisonment or additional fines. The exact penalties depend on the severity and circumstances of the non-compliance, but the potential consequences are significant, underscoring the importance of adherence to the specified requirements.