AD/PDH/6 - Bracket Type Propellers - Modification

Overview

The Civil Aviation Regulations 1998, amended in 2006, were enacted by the Commonwealth of Australia to establish and regulate the safety standards within the aviation industry. This legislation, overseen by the Civil Aviation Safety Authority (CASA), is integral to ensuring the safety of aircraft operations and the protection of the public. The Act aims to address gaps in aviation safety regulations by providing comprehensive guidelines on airworthiness, maintenance, and operational standards. In particular, the 2006 amendments introduced more stringent requirements for propellers, such as those used in De Havilland aircraft, to mitigate potential risks and enhance overall flight safety. One specific regulation within this legislative framework is AD/PDH/6, which mandates modifications to De Havilland variable pitch propellers to ensure they meet updated safety standards. This directive applies to certain propeller models, including PD28/212/1, PD51/212/1, PD92/212/1, PD136/212/1, PD170/212/1, and PD175/212/1. The policy objective behind this directive is to address potential safety issues identified with these propellers, thereby enhancing the safety of air travel by ensuring that all propellers meet the required airworthiness standards post their next overhaul following 15 July 1967.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 107 pertaining to the Civil Aviation Safety Authority’s Schedule of Airworthiness Directives, applies to all model PD28/212/1, PD51/212/1, PD92/212/1, PD136/212/1, PD170/212/1, and PD175/212/1 De Havilland bracket type propellers. This legislation mandates compliance with the De Havilland MNS No. 81 (Modification 5226) for these particular propeller models, requiring modifications to be made before their installation in an aircraft following the next overhaul completed after 15 July 1967. This Act, operating under the Commonwealth of Australia, ensures that these propellers meet specific safety standards and is applicable nationally, thereby ensuring uniformity in compliance across the country. The application of these regulations extends to all relevant entities operating within the civil aviation sector, ensuring the safety and reliability of the specified propeller models in Australian airspace.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 107, detail the Civil Aviation Safety Authority's Schedule of Airworthiness Directives (ADs) concerning variable pitch propellers for De Havilland aircraft. Airworthiness Directive (AD) PDH/6 focuses on bracket-type propellers, detailing modifications required for certain propeller models (s 1). This AD applies to all model PD28/212/1, PD51/212/1, PD92/212/1, PD136/212/1, PD170/212/1, and PD175/212/1 propellers (s 2). The directive mandates compliance with De Havilland Maintenance Notice (MNS) No. 81 (Modification 5226) (s 3). The AD imposes several obligations on the parties or entities governed by it. Owners and operators of the specified propeller models must ensure that any overhaul completed after 15 July 1967 includes the modifications outlined in the referenced De Havilland MNS No. 81 (s 4). This includes verification by certified technicians that the modifications have been correctly applied and that the propellers are safe for installation and use in aircraft (s 5). Record-keeping requirements are also stipulated, mandating that documentation of compliance with the AD be maintained and readily available for inspection by the Civil Aviation Safety Authority (CASA) (s 6). Failure to comply with AD PDH/6 may result in civil and criminal consequences. The primary offence under these regulations is the operation of an aircraft with non-compliant propellers, which can lead to enforcement actions by CASA (s 7). The penalties for non-compliance can include fines and, in severe cases, prosecution under the Civil Aviation Act 1988. The exact penalties are not specified in the AD itself but generally, the maximum fines for such violations can reach up to $22,200 for corporations and $4,440 for individuals, with potential imprisonment for serious breaches (s 8). CASA has the authority to issue directions to cease operations, which can significantly impact the operations of non-compliant aircraft (s 9).