COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
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.
DHC-6 (Twin Otter) Series Aeroplanes
AD/DHC-6/73 Wing Spar Strut Lug 12/2002
Applicability: Model DHC-6 Series 1, 100, and 200 aircraft, with PreMod 6/1117 wings that have accumulated less than 17,400 flight hours or 34,800 flight cycles.
Requirement: 1. Conduct a high frequency eddy current inspection of the wing spar strut lug fastener holes. Perform the inspection in accordance with the wing spar strut lug fastener hole inspection procedure detailed in Part 3, Inspection Requirements Manual - PSM 1-6-7.
2. Assess the results and comply with any additional action required in accordance with the acceptance/rejection criteria detailed in the wing spar strut lug fastener hole inspection of Part 3, Inspection Requirements Manual - PSM 1-6-7.
3. If corrosion, cracking or damage is found in any fastener hole, report findings to Bombardier within 14 days of the inspection.
Note: Transport Canada AD CF-2002-40 refers.
Compliance: Within 12 months after 28 November 2002. Thereafter at intervals not to exceed 10 years.
This Airworthiness Directive becomes effective on 28 November 2002.
Background: Non-destructive testing inspection of the wing spar strut fastener holes of several aircraft with PreMod 6/1117 wings has revealed corrosion in the critical fastener holes. While the inspection of these critical holes is addressed under AD CF-2000-14 (AD/DHC-6/31), some low-utilisation aircraft have yet to reach the fatigue based inspection threshold of 17,400 flight hours or 34,800 flight cycles. Undetected corrosion in the critical fastener holes could lead to lug cracking, compromising the structural integrity of the wing.
David Alan Villiers
Delegate of the Civil Aviation Safety Authority 21 October 2002
The above AD is notified in the Commonwealth of Australia Gazette on 6 November 2002.
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Overview
The Civil Aviation Regulations 1998, as amended, contain a specific Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority (CASA) under subregulation 39.1(1). This particular AD, titled "AD/DHC-6/73 Wing Spar Strut Lug 12/2002", was enacted to address the issue of corrosion and structural integrity concerns identified in the wing spar strut fastener holes of certain DHC-6 Twin Otter Series aeroplanes. The policy objective behind this AD is to ensure the safety of aircraft by mandating regular inspections and corrective actions to prevent any unsafe conditions that could arise from undetected corrosion or damage in critical fastener holes. The directive applies to Model DHC-6 Series 1, 100, and 200 aircraft equipped with PreMod 6/1117 wings, provided they have accumulated less than 17,400 flight hours or 34,800 flight cycles. The AD requires operators to conduct a high frequency eddy current inspection of the wing spar strut lug fastener holes, assess the results, and report any findings to Bombardier within a specified timeframe. Failure to comply with this directive could potentially compromise the aircraft’s structural integrity, thereby posing a significant safety risk.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39, contains an Airworthiness Directive (AD) aimed at ensuring the safety of certain aircraft models. This AD applies to DHC-6 Series 1, 100, and 200 aeroplanes with PreMod 6/1117 wings that have accumulated less than 17,400 flight hours or 34,800 flight cycles. The directive mandates a high-frequency eddy current inspection of the wing spar strut lug fastener holes to detect any signs of corrosion, cracking, or damage, and requires reporting of findings to Bombardier within 14 days if any issues are discovered. Compliance with the AD is mandatory and must be achieved within 12 months of the directive's effective date, 28 November 2002, and subsequently at intervals not exceeding 10 years. This directive is an instrument of the Civil Aviation Safety Authority (CASA), reflecting the Commonwealth's commitment to maintaining stringent safety standards in civil aviation.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, contain an Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority (CASA). This AD, labelled AD/DHC-6/73, pertains to the DHC-6 (Twin Otter) Series 1, 100, and 200 aircraft equipped with PreMod 6/1117 wings that have accumulated less than 17,400 flight hours or 34,800 flight cycles. The AD requires that a high-frequency eddy current inspection be conducted on the wing spar strut lug fastener holes, as outlined in Part 3, Inspection Requirements Manual - PSM 1-6-7. This inspection must be carried out in accordance with the detailed inspection procedure and acceptance/rejection criteria provided in the manual. If any corrosion, cracking, or damage is detected in the fastener holes during the inspection, the findings must be reported to Bombardier within 14 days.
The AD imposes several obligations on the parties governed by it. Primarily, aircraft operators and owners must ensure that the specified inspections are performed by qualified personnel following the detailed procedures and criteria outlined in the Inspection Requirements Manual. This includes conducting the eddy current inspection and assessing the results against the acceptance/rejection criteria. Additionally, if any corrosion, cracking, or damage is identified in the fastener holes, operators are required to report these findings to Bombardier within the stipulated timeframe of 14 days. Failure to comply with these requirements may result in non-compliance with the AD and could potentially lead to safety issues.
Breach of the requirements set out in this AD can lead to various civil and criminal consequences. The primary consequence is the potential for the aircraft to be deemed unairworthy if the specified inspections and corrective actions are not performed. This could result in grounding of the aircraft until compliance is achieved. Furthermore, non-compliance with the AD can lead to enforcement actions by CASA, which may include fines and other penalties. While the maximum penalties are not specified in the AD itself, CASA has the authority to impose fines up to a certain limit under the Civil Aviation Act 1988 and other related legislation. In severe cases, non-compliance could also lead to criminal charges against the operators or individuals responsible for the oversight of the aircraft.