AD/PDH/4 - Model 4/4000/6 Blade - Modification

Overview

The Civil Aviation Regulations 1998, amended by the legislative instrument F2006B06163, address specific issues related to the airworthiness of propellers in De Havilland aircraft models. Enacted by the Australian Government, this regulation was introduced to ensure safety and compliance with international aviation standards, specifically targeting variable pitch propellers. The objective of this regulation is to mitigate risks associated with the installation of blades on De Havilland PD66/446/2 and PD96/446/1 propellers by mandating compliance with prescribed modifications before the propellers are installed in an aircraft. This is achieved through adherence to either DH MHS Series 4HF No. 118 or ANO 107.1.4.9.5.1, ensuring that all components meet the necessary safety standards to prevent potential hazards during flight.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 107, outlines the requirements for airworthiness directives that must be followed to ensure the safety of aircraft operations within Australian airspace. Airworthiness Directive (AD) PDH/4 pertains to the modification of blades on De Havilland model 4/4000/6 blade variable pitch propellers, types PD66/446/2 and PD96/446/1. This directive applies to all blades fitted to these specified propeller types and mandates compliance before installation in an aircraft. Compliance with AD/PDH/4 is critical for maintaining the airworthiness of the aircraft and ensuring safety standards are met as per the Civil Aviation Safety Authority's regulations. The directive's applicability is governed by the 1998 Civil Aviation Regulations and can be referenced through DH MHS Series 4HF No. 118 or ANO 107.1.4.9.5.1. This regulation extends across the Commonwealth of Australia, affecting all operators and maintainers of the specified propeller types within the national airspace.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 107 Civil Aviation Safety Authority Schedule of Airworthiness Directives, section AD/PDH/4, pertains to the modification of variable pitch propellers for De Havilland Model 4/4000/6 blade propellers (section 1). This section applies to all blades fitted to the types PD66/446/2 and PD96/446/1 propellers (section 2). Compliance with this directive is mandatory and must be achieved before the propeller blades are installed in an aircraft (section 3). The directive references two documents for compliance: DH MHS Series 4HF No. 118, or ANO 107.1.4.9.5.1 (section 4). The obligations imposed by this Act on the parties involved include ensuring that all modifications to the specified propeller blades are carried out in accordance with the detailed instructions provided in the referenced documents. Operators, maintenance organisations, and individuals responsible for the maintenance or modification of these propellers must adhere strictly to the outlined procedures to maintain airworthiness standards. This includes the requirement to use the specified documents as the primary guide for any modifications to ensure that the propellers meet the necessary safety standards before being reintroduced into service. Failure to comply with the provisions of section AD/PDH/4 may result in severe consequences. The Act does not explicitly state any specific offences or penalties within the provided text; however, non-compliance with airworthiness directives typically results in penalties under the Civil Aviation Act 1988. The potential penalties for breaching airworthiness requirements can include fines and imprisonment. Under the Civil Aviation Act 1988, an individual found guilty of a serious breach of air safety regulations can face a maximum penalty of two years imprisonment or a fine of up to $22,000, or both. For corporate entities, the maximum penalty can be significantly higher, often reaching up to $1,100,000. Additionally, any failure to comply can result in the grounding of aircraft until the required modifications are completed, potentially leading to significant operational disruptions and financial losses.