COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Lycoming Piston Engines
AD/LYC/71
Amdt 1
Pushrod - Inspection 3/81
Applicability: 0-235 series engines with S/Nos. L-12500-15 to L-20676-15 inclusive, all Lycoming remanufactured 0-235 series engines, regardless of S/No., shipped between 10 December 1976 and 8 November 1979, and all 0-235 series engines regardless of S/No., that had pushrods replaced between 10 December 1976, and 24 November 1980. This AD does not apply to engines incorporating eight pushrods identified by revision letter K or subsequent revision letter, or by Code T-T, -85, or the symbol # as described in SB No. 453A.
Requirement: Part 1 - Remove all eight pushrods and inspect for loose ball ends and evidence of bulging and splitting of the pushrod tubing. Measure the length of the pushrod assembly. The overall length shall not be less than 11-17/32 inches. If all these conditions are satisfactory, set valve clearances in accordance with Para. 8 of Lycoming SI Nos. 1388A dated 25 January 1980, and 1068A dated 1 September 1978. If any pushrod is found damaged or is less than the specified dimension noted above, replace with a serviceable part prior to further flight.
Part 2 - Measure and record valve tappet clearance in accordance with Lycoming SI Nos. 1388A and 1068A. If any valve clearance increases more than .015 inch since the last 25 hour inspection, remove the pushrod and inspect for damage and shortening in accordance with Item 1 above.
Compliance: Part 1 - Within 25 hours time in service after 31 March 1981 or before 14 April 1981, whichever occurs first.
Part 2 - Within 25 hours time in service after 31 March 1981 or before 14 April 1981 whichever occurs first and thereafter at intervals not exceeding 25 hours time in service.
Note: Engines complying with the initial issue of this Directive satisfy the requirements of this issue of the Directive.
Background: This Directive is raised in issue to reflect the following changes:
(a) Engines of Serial Numbers Listed in Lycoming SB No. 435A as exempt from compliance are now also affected.
(b) FAA Directive No. 80-25-02, Rev. 2 forms the basis of this Directive. Overseas reports show one recent fatal accident attributable to this problem and in excess of 80 reports of failed pushrods found in service. A number of local defects have also occurred.
Inspection of suspect pushrods is therefore necessary to prevent failure.
It is known that Ansett General Aviation Bankstown have the necessary tooling to inspect pushrods and reidentify as a -85 suffix to the part number.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Overview
The Civil Aviation Regulations 1998, as amended, include provisions designed to ensure the safety and reliability of aviation components, particularly under the authority of the Civil Aviation Safety Authority (CASA). One such regulation, AD/LYC/71Amdt 1, was introduced to address issues identified with the pushrods of Lycoming 0-235 series piston engines. This Airworthiness Directive was enacted to mitigate the risks associated with potential pushrod failure, which could lead to engine malfunction and, in severe cases, catastrophic accidents. CASA’s primary policy objective in issuing this directive was to enhance aviation safety by mandating regular inspections and maintenance of specified Lycoming piston engine pushrods, ensuring they meet required specifications and are free from defects. The directive applies to a specific range of engine serial numbers and mandates inspections and corrective actions to be performed within specified timeframes.
Scope and Application
The Civil Aviation Regulations 1998, specifically PART 39 - 106 Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to Lycoming 0-235 series piston engines with specific serial numbers and those remanufactured between particular dates, as well as all 0-235 series engines that had their pushrods replaced within certain timeframes. This regulation is designed to ensure the safety of aircraft operations by mandating inspections and maintenance actions on identified pushrods to prevent potential failures. The regulation does not apply to engines with eight pushrods that are identified by certain revision letters or codes, as detailed in Service Bulletin No. 453A. The inspection and maintenance requirements outlined in this directive are jurisdictional within Australia, aligning with international standards set by the Federal Aviation Administration, and are enforced to mitigate risks associated with pushrod failures, which have been linked to accidents and numerous service incidents.
Key Provisions
The Civil Aviation Regulations 1998, under Part 39 - 106, specifies certain airworthiness directives for Lycoming piston engines, particularly focusing on pushrod inspections for the 0-235 series engines. Section (AD/LYC/71Amdt 1) outlines the applicability of this directive, which targets specific serial numbers and manufacturing dates of the engines. Notably, it does not apply to engines that have eight pushrods identified by certain revision letters or codes, as detailed in Service Bulletin No. 453A. The directive requires a thorough inspection of the pushrods to check for loose ball ends, bulging, splitting, and to ensure the pushrod assembly meets the specified length of 11-17/32 inches (section 3/81). If any issues are detected, the pushrods must be replaced with serviceable parts before further flight. Additionally, it mandates measuring and recording the valve tappet clearance, as per Lycoming Service Instructions Nos. 1388A and 1068A, and further inspection if any valve clearance exceeds a specified increment.
Compliance with these provisions is mandatory for all affected aircraft operators. Specifically, Part 1 of the directive requires that all inspections and necessary actions are completed within 25 hours of time in service after 31 March 1981, or before 14 April 1981, whichever comes first. Part 2 of the directive mandates that inspections should be performed within the same timeframe and then at intervals not exceeding 25 hours of time in service. It is noteworthy that engines that were compliant with the initial issue of this directive continue to meet the requirements of the current directive.
Failure to adhere to these airworthiness directives can result in serious consequences. Given the safety implications highlighted in the directive, such as fatal accidents and numerous reports of failed pushrods, non-compliance could lead to severe penalties. The specific civil or criminal consequences for breach are not explicitly stated in the provided text, but it is clear that the regulations are enforced to prevent potential hazards and ensure the safety of air travel. The directive is based on the Federal Aviation Administration's Directive No. 80-25-02, Rev. 2, reflecting a collaborative approach to aviation safety across jurisdictions.