AD/DHC-6/10 - Left Hand Elevator Trim Tab - Replacement

Overview

The Civil Aviation Regulations 1998 were enacted to regulate civil aviation in Australia, ensuring safety and efficiency in the operation of aircraft. This legislation, which was introduced by the Australian Government and administered by the Civil Aviation Safety Authority (CASA), aims to establish and maintain a high standard of safety and security in civil aviation. The problem it addresses includes the need for clear and consistent regulations to govern the operation of aircraft within Australian airspace, ensuring that all aviation activities comply with stringent safety standards. The policy objective of these regulations is to protect the public and promote safe, orderly, and economical use of the airspace. The specific legislative instrument F2006B09097 focuses on the airworthiness directives for the DHC-6 (Twin Otter) Series Aeroplanes, mandating the replacement of the left-hand elevator trim tab for all models with serial numbers 1 to 87. This directive is in compliance with De Havilland of Canada Modification Bulletin 6/1120 and must be implemented before 1 April 1968. This measure is part of the broader regulatory framework designed to enhance the safety and reliability of aircraft operations by addressing specific design and maintenance issues identified in certain aircraft models.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the Airworthiness Directives for DHC-6 (Twin Otter) Series Aeroplanes, with a particular focus on the left-hand elevator trim tab replacement as outlined in AD/DHC-6/10. This legislation applies to all DHC-6 Twin Otter aeroplanes with serial numbers from 1 to 87, mandating compliance with the directive before 1 April 1968, as referenced in De Havilland of Canada Modification Bulletin 6/1120. The directive is overseen by the Civil Aviation Safety Authority (CASA) and is enforceable across the Commonwealth of Australia, ensuring that all specified aircraft meet the specified airworthiness standards. The regulation does not explicitly state any exclusions, exemptions, or thresholds, but its application can be extended or further defined through subordinate instruments issued by CASA.

Key Provisions

The Civil Aviation Regulations 1998, specifically under Part 39 - 105, contain the Civil Aviation Safety Authority's (CASA) Schedule of Airworthiness Directives for the DHC-6 (Twin Otter) Series Aeroplanes. This particular directive, AD/DHC-6/10, pertains to the left-hand elevator trim tab and mandates its replacement (Section 1/68). The applicability of this directive extends to all models with serial numbers from 1 to 87. Compliance with this directive was required before 1 April 1968, as outlined in the De Havilland of Canada Modification Bulletin 6/1120. For entities governed by these regulations, the obligations include ensuring that all specified DHC-6 Twin Otter aircraft with the given serial numbers undergo the mandatory replacement of the left-hand elevator trim tab. This requirement ensures that the aircraft meet the specified airworthiness standards and maintain operational safety as set forth by CASA. Operators must also ensure that any modifications or replacements are documented and certified by CASA-approved personnel. Failure to comply with the directive can result in severe consequences. Under Section 91.1 of the Civil Aviation Act 1988, non-compliance may be considered an offence, potentially leading to penalties that can include fines or other legal repercussions. The exact penalties may vary based on the severity of the breach, but the overarching goal is to ensure that all aircraft meet the required safety standards. Furthermore, continued operation of a non-compliant aircraft could result in CASA taking enforcement actions, including grounding the aircraft until the required modifications are completed and certified.