AD/PHZL/66 - Blade Pitch Change Knob

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 107, was enacted to maintain and enforce safety standards in civil aviation within Australia. This legislative instrument addresses potential safety risks associated with aircraft components, including propellers. The problem it aims to resolve involves the risk of the pitch change knob on Hartzell model HC-E4A-3A/E10950 propellers detaching due to screw failure, which could lead to dangerous vibrations and complete failure of the propeller to feather properly. The Australian Parliament enacted these regulations to ensure that air travel remains safe and reliable, aligning with the overarching policy objective of protecting public safety in civil aviation. The Civil Aviation Safety Authority is responsible for overseeing compliance with these regulations, ensuring that aircraft and their components meet necessary safety standards. The specific directive, AD/PHZL/66, mandates compliance with the requirement to address the pitch change knob issue on affected propellers, referencing the Hartzell Alert Service Bulletin A190 and FAA AD 94-10-01 Amdt 39-8908. This directive became effective from 6 July 1994, reinforcing the commitment to maintaining high safety standards in civil aviation.

Scope and Application

The Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998, specifically within Part 39 and the Schedule of Airworthiness Directives, mandates strict compliance concerning certain aircraft components. For instance, AD/PHZL/66 addresses all model HC-E4A-3A/E10950 propellers, serial numbers up to and including HJ198, installed on Beech 1900D aircraft. The directive requires adherence to the blade pitch change knob specifications unless previous corrective actions have been executed in line with Hartzell Alert Service Bulletin A190. This regulatory action is intended to prevent the failure of pitch change knob attachment screws, which could otherwise result in dangerous vibration and the propeller feathering completely, posing significant safety risks. The directive references FAA AD 94-10-01 Amendment 39-8908 and must be complied with as detailed in the requirement document, effective from 6 July 1994. The applicability of this directive is limited to the specified propeller models and aircraft type, ensuring that only those within the prescribed scope are subject to compliance measures. The directive applies on a national level, overseen by CASA, and is part of a broader framework aimed at maintaining the highest standards of aviation safety across Australia. The directive does not specify any exclusions or exemptions, indicating that all affected aircraft must adhere to the prescribed requirements without exception. The enforcement and detailed specifications are further managed through subordinate instruments, which may expand upon or refine the directive’s application in practice.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 107, includes Airworthiness Directives (AD) which are binding orders to address safety issues in civil aviation. AD/PHZL/66 pertains to Hartzell propellers, particularly the blade pitch change knob on model HC-E4A-3A/E10950 propellers (section 9/94 DMApplicability). This directive applies to all such propellers, up to and including serial number HJ198, that are installed on Beech 1900D aircraft. It mandates compliance with Hartzell Alert Service Bulletin A190, unless the required actions have already been performed (section Requirement). Under this directive, the primary obligation is to ensure the blade pitch change knob attachment screws are secure and not prone to failure. The directive emphasises the importance of adhering to the Requirement Document, which was effective from 6 July 1994. This is to prevent potential issues such as vibrations and unintended feathering of the propeller, which could compromise flight safety (section Compliance). The directive references FAA AD 94-10-01 Amdt 39-8908, highlighting the collaborative nature of international aviation safety regulations. Failure to comply with this Airworthiness Directive can have serious repercussions. While the specific penalties are not detailed in the excerpt, non-compliance with ADs typically leads to enforcement actions by the Civil Aviation Safety Authority (CASA). This may include fines, suspension or revocation of aircraft operating certificates, and potential criminal charges in cases of gross negligence or wilful disregard for safety regulations. The exact penalties depend on the severity and impact of the non-compliance, but the overarching goal is to ensure that all safety directives are adhered to rigorously to maintain the highest standards of aviation safety (section Background).