COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Propellers - Variable Pitch - Hartzell
AD/PHZL/72 Counterweight Clamp Bolt Hole 12/98
Applicability: Hartzell Propeller Inc. HC-E4A-3(A,I,J) series propellers, with serial numbers HJ1 through HJ1040, that have been previously overhauled or have had a counterweight clamp bolt removed for any reason.
Requirement: Unless previously accomplished:
Perform a one time inspection of the propeller blade counterweight clamps for thread damage in the bolt holes in accordance the Accomplished Instructions of the Hartzell Propeller Inc. Alert Service Bulletin (ASB) No. HC-ASB-61-237, dated 17 July,1998. The replacement or re-assembly of propeller blade counterweight clamps is to be carried out in accordance with ASB No. HC-ASB-61-237, dated 17 July 1998.
Compliance: 1. For propellers with 2,500 or more hours time in service (TIS) since last overhaul, inspect within 300 hours TIS, or 45 days after the effective date of this AD, whichever occurs first.
2. For all other propellers inspect within 600 hours TIS, or 90 days after the effective date of this AD, whichever occurs first.
This Airworthiness Directive becomes effective on 5 November 1998.
Background: There has been previous reports of thread damage caused by bolt hole failure and thread damage by cross threading, this damage has lead to counterweight separation in flight.
Overview
The Civil Aviation Regulations 1998, amended by the Commonwealth of Australia through the Civil Aviation Safety Authority, address the critical issue of ensuring the safety and airworthiness of propellers, particularly those from Hartzell Propeller Inc. This legislation was introduced to mitigate risks associated with thread damage in bolt holes and subsequent counterweight separation during flight, which could potentially lead to catastrophic failures. The overarching policy objective is to enhance the safety standards of civil aviation by mandating specific inspections and maintenance procedures for certain propellers. The Airworthiness Directive AD/PHZL/72, effective from 5 November 1998, outlines a mandatory one-time inspection of Hartzell HC-E4A-3(A,I,J) series propellers for thread damage in the bolt holes, with specific timelines based on the time in service of the propellers. This directive ensures that any identified issues are addressed promptly, thereby maintaining the highest standards of aviation safety.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 107, applies to the Hartzell Propeller Inc. HC-E4A-3(A,I,J) series propellers with serial numbers HJ1 through HJ1040, which have undergone previous overhauls or had their counterweight clamp bolts removed for any reason. This legislation mandates a one-time inspection of the propeller blade counterweight clamps to check for thread damage in the bolt holes, as outlined in the Accomplished Instructions of Hartzell Propeller Inc. Alert Service Bulletin (ASB) No. HC-ASB-61-237, dated 17 July 1998. The replacement or re-assembly of the counterweight clamps must also adhere to the same bulletin. Compliance with this directive requires inspections within specific timeframes based on the propeller's time in service since the last overhaul, with inspections for propellers having 2,500 or more hours time in service (TIS) since the last overhaul to be conducted within 300 hours TIS or 45 days after the directive's effective date, whichever comes first, and for all other propellers within 600 hours TIS or 90 days after the effective date, whichever is sooner. This Airworthiness Directive became effective on 5 November 1998, following reports of thread damage and bolt hole failures that resulted in counterweight separation during flight.
Key Provisions
The Civil Aviation Regulations 1998, under Part 39 and specifically in section 107, include provisions concerning the airworthiness of aircraft propellers. In this context, AD/PHZL/72 pertains to Hartzell propellers, specifically those in the HC-E4A-3 series with certain serial numbers (HJ1 through HJ1040) that have undergone overhaul or had a counterweight clamp bolt removed. The directive mandates a one-time inspection of these propellers for thread damage in the bolt holes of the counterweight clamps. This inspection is to be conducted in accordance with the instructions provided in Hartzell Propeller Inc. Alert Service Bulletin (ASB) No. HC-ASB-61-237 dated 17 July 1998. Any replacement or re-assembly of the propeller blade counterweight clamps must also follow the guidelines in this bulletin.
The obligations imposed by this directive require operators of the specified propellers to ensure that inspections and any necessary repairs are carried out within specific timeframes. For propellers with 2,500 or more hours of time in service (TIS) since the last overhaul, the inspection must be completed within 300 hours TIS or 45 days from the effective date of the Airworthiness Directive (AD), whichever comes first. For all other propellers, the inspection must occur within 600 hours TIS or 90 days from the effective date of the AD, whichever is sooner. This directive came into effect on 5 November 1998.
Failure to comply with the requirements set forth in this Airworthiness Directive could result in serious safety hazards. The background information provided indicates that there have been previous incidents of thread damage caused by bolt hole failure and cross threading, which have led to counterweight separation during flight. These issues underscore the importance of adhering to the inspection and repair guidelines to prevent such incidents. While the specific civil or criminal consequences for non-compliance are not detailed in the excerpt, it is reasonable to infer that failure to comply with such safety directives could result in severe penalties, including fines or legal action against the operator or owner of the aircraft.