COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
De Havilland DHC-1 (Chipmunk) Series Aeroplanes
AD/DHC-1/12
Amdt 6
Applicability: All models.
Wing Spar Booms and Centre Section - Fatigue Life Limitation
8/86
Requirement: Retire the wing spar boom and centre section components in accordance with British Aerospace (Hawker Siddeley) TNS CT (C1) No. 138 Issue 5.
Note 1: With regard to the light alloy wing root insert fittings (para 2.3 of TNS 138), the inspection, reaming and re- bushing operation of TNS 160 may only be carried out once.
Note 2: With regard to the steel centre-section lower tie-bar (para 2.2 of TNS 138), it will be necessary to perform an inspection in accordance with TNS 175 to determine which retirement life is applicable.
Compliance: As detailed in the Requirement Document.
Note 1: The Role Factor classifications of TNS 138 shall be determined in consultation with the appropriate Regional Office. However, notwithstanding the provisions of TNS 138, in all future assessments a Role Factor of 2.5 shall be assigned to Glider Towing operations.
Note 2: The life limitations given in TNS 138 are directly applicable to British built DHC-1 aircraft, but are not directly applicable to Canadian built aircraft which are structurally significantly different in the fatigue critical locations. Owners/operators of Canadian built aircraft must contact the Secretary, through any Regional office of the Department, for a fatigue life assessment.
Background: Australian recorded flight loads data show that Glider Towing is a more severe fatigue environment than that indicated by TNS 138.
The fatigue lives given in TNS 138 are based on fatigue testing of a British built aircraft. Canadian built aircraft are structurally different from British aircraft and could also differ from one another in build standard and modification status. Each Canadian aircraft must therefore be assessed individually. The only Canadian aircraft assessed at the time of issue of this amendment showed fatigue lives comparable to those in TNS 138.
Overview
The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the safety standards for civil aircraft operations within Australia through the Civil Aviation Safety Authority (CASA). This legislation was enacted to ensure that all civil aviation activities within Australia adhere to stringent safety standards and protocols. One such regulation, AD/DHC-1/12 Amendment 6, focuses on the applicability of fatigue life limitations for the De Havilland DHC-1 (Chipmunk) Series Aeroplanes, particularly the wing spar booms and centre section. This amendment was introduced to address the identified problem of fatigue in these components, which is exacerbated by activities such as glider towing, as observed in Australian flight data. The policy objective is to mandate the retirement of these components in accordance with British Aerospace guidelines, while also allowing for individual assessments of Canadian-built aircraft due to structural differences.
The Civil Aviation Regulations 1998 are administered by CASA, which is tasked with ensuring compliance with these safety directives. The amendment highlights the need for specific inspections and operational limitations, particularly for Canadian-built DHC-1 aircraft, which may require individual assessments due to their structural differences from British-built models. The regulations aim to mitigate the risks associated with fatigue in the identified components, thereby enhancing the overall safety of civil aviation operations in Australia.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, applies to all De Havilland DHC-1 (Chipmunk) Series Aeroplanes in Australia, governing their airworthiness directives. This regulation mandates the retirement of wing spar boom and centre section components in accordance with British Aerospace (Hawker Siddeley) Technical Notice CT (C1) No. 138 Issue 5. It is crucial for the owners and operators of these aircraft to adhere to the specified requirement document, with certain notes detailing particular operations such as the inspection and reaming of light alloy wing root insert fittings and the inspection of the steel centre-section lower tie-bar. The application of these directives extends across all models of the DHC-1 series, with specific adjustments for Canadian built aircraft, which require individual assessments due to structural differences from British built aircraft. This regulation's scope and application are enforced under the jurisdiction of the Commonwealth of Australia and may be further detailed or amended through subordinate instruments.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, contain the Civil Aviation Safety Authority’s Schedule of Airworthiness Directives for De Havilland DHC-1 (Chipmunk) Series Aeroplanes. One of these directives, AD/DHC-1/12 Amendment 6, pertains to the wing spar booms and centre section fatigue life limitation (Section 8/86). This section requires all models of the De Havilland DHC-1 aeroplanes to retire the wing spar boom and centre section components in accordance with British Aerospace (Hawker Siddeley) Technical Notice Series (TNS) CT (C1) No. 138 Issue 5. The specific requirement for light alloy wing root insert fittings, as mentioned in paragraph 2.3 of TNS 138, allows for inspection, reaming, and re-bushing only once, as per TNS 160. Similarly, the steel centre-section lower tie-bar, covered under paragraph 2.2 of TNS 138, requires inspection in accordance with TNS 175 to determine the applicable retirement life.
The Act imposes several obligations on the parties governed by it. Primarily, it mandates the retirement of specified components in line with the referenced technical notices and standards, ensuring that the aircraft remain airworthy and safe to operate. It also necessitates compliance with Role Factor classifications as detailed in TNS 138, with a specific Role Factor of 2.5 for Glider Towing operations. Owners and operators are required to consult with the appropriate Regional Office for determining these classifications. Additionally, for Canadian-built aircraft, which differ structurally from British-built ones, individual fatigue life assessments must be sought from the Secretary through any Regional Office of the Department.
Failure to comply with the directives may result in serious consequences. The Civil Aviation Regulations 1998 do not explicitly outline penalties within the text of this specific directive. However, non-compliance with airworthiness directives generally may lead to enforcement actions, including fines, suspension, or revocation of the aircraft’s airworthiness certificate. Additionally, there may be civil or criminal liability for any accidents or incidents that result from non-compliance. The potential maximum penalties for breaches of airworthiness regulations can vary, but they generally include significant financial penalties and possible imprisonment, depending on the severity of the breach and its consequences.