COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Boeing 727 Series Aeroplanes
AD/B727/113 Aft Mount Support Fittings Engines 1 and 3 2/90
Applicability: All models.
Requirement: Action in accordance with Boeing SB 727-54-0017.
Note: FAA AD 89-23-17 refers.
Compliance: 1. For aircraft with fittings made of 7079-T6 material. Unless previously accomplished within the last 2000 flight cycles prior to 22 February 1990 - Prior to exceeding 1000 flight cycles or 1 year after 22 February 1990, whichever occurs first, and thereafter at intervals not exceeding 3000 flight cycles.
Note: 7079-T6 material is used in the aft support fitting on number 1 engine strut on aircraft line numbers 001 through 883, and number 3 engine strut on aircraft line number 001 through 880.
2. For aircraft with fittings made of 7075-T73 material. Unless previously accomplished within the last 2000 flight cycles prior to 22 February 1990 - Prior to exceeding 40,000 flight cycles, or within 1000 flight cycles after 22 February 1990 whichever occurs later, and thereafter at intervals not exceeding 3000 flight cycles.
Note: 7075-T73 material is used in the aft support fitting on number 1 engine strut on aircraft line number 884 and later, and on number 3 engine strut on aircraft line number 881 and later.
Background: Country of origin AD. Cracking has been reported as a result of stress corrosion and fatigue.
Overview
The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority (CASA) under the Civil Aviation Act 1988, are designed to ensure the safety of civil aviation within Australia. One particular aspect of these regulations, specified in Part 39 - 105, pertains to Airworthiness Directives for various aircraft, including the Boeing 727 Series Aeroplanes. The directive AD/B727/113, issued on 2 February 1990, addresses the issue of stress corrosion and fatigue in the aft mount support fittings of engines 1 and 3 of Boeing 727 aircraft. The directive mandates specific maintenance actions in accordance with Boeing Service Bulletin 727-54-0017, referencing FAA AD 89-23-17, to mitigate the risk of cracking in these critical components, thereby enhancing the overall airworthiness and safety of the aircraft.
The policy objective underpinning this directive is to ensure that the identified safety risks are effectively managed, thereby protecting the safety of passengers, crew, and the general public. The directive stipulates different compliance timelines and intervals for aircraft based on the material used in the aft support fittings, aiming to maintain the structural integrity of the aircraft and prevent potential catastrophic failures due to stress corrosion and fatigue.
Scope and Application
The Civil Aviation Regulations 1998, under the jurisdiction of the Civil Aviation Safety Authority, apply to all Boeing 727 series aeroplanes regarding the maintenance of aft mount support fittings for engines 1 and 3. This regulation mandates adherence to Boeing Service Bulletin 727-54-0017, which addresses issues of stress corrosion and fatigue that may lead to cracking in the fittings. The regulation applies to aircraft with fittings made of 7079-T6 and 7075-T73 materials, with specific timelines and intervals for inspections and maintenance based on the material type and aircraft line number. Compliance must be achieved for aircraft with 7079-T6 material fittings within certain flight cycle limits and timeframes post-22 February 1990, while those with 7075-T73 material fittings have different criteria. The regulation's applicability extends to all models of the Boeing 727 series within Australia and aligns with international standards set by the Federal Aviation Administration through FAA AD 89-23-17. The regulation may be further refined or expanded through subordinate instruments issued by the Civil Aviation Safety Authority.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39, Section 105, includes a directive concerning the airworthiness of Boeing 727 Series aeroplanes. This directive, identified as AD/B727/113, pertains to the aft mount support fittings on engines 1 and 3. The requirement outlined in the directive necessitates compliance with Boeing Service Bulletin 727-54-0017, with reference to the Federal Aviation Administration's AD 89-23-17. This directive applies to all models of Boeing 727 aeroplanes. The directive mandates specific actions to be taken regarding the aft mount support fittings based on the material used in the fittings: 7079-T6 or 7075-T73.
The obligations imposed by this directive are quite specific. For aircraft equipped with fittings made of 7079-T6 material, inspections must be conducted prior to exceeding 1000 flight cycles or one year after 22 February 1990, whichever comes first, unless the inspection has already been completed within the last 2000 flight cycles prior to that date. After this initial inspection, subsequent inspections must occur at intervals not exceeding 3000 flight cycles. For aircraft with fittings made of 7075-T73 material, the inspection must be carried out before the aircraft accumulates 40,000 flight cycles or within 1000 flight cycles after 22 February 1990, whichever is later. Following this initial inspection, further inspections must occur at intervals not exceeding 3000 flight cycles.
Failure to comply with the directives outlined in AD/B727/113 may result in serious safety implications due to the reported issues of stress corrosion and fatigue leading to cracking in the aft mount support fittings. The Civil Aviation Regulations do not explicitly state specific penalties or consequences for non-compliance within the provided text; however, non-compliance with airworthiness directives generally results in severe civil or criminal penalties, including fines and potential grounding of the aircraft until compliance is achieved. Such non-compliance can also result in significant safety risks, potentially endangering lives and property.