COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Pratt and Whitney Turbine Engines - JT8D Series
AD/JT8D/24
Amdt 1
Seventh Stage Compressor Airseal 2/90
Applicability: JT8D-1, -1A, -1B, -7, -7A, -7B,-9, -9A, -11, -15, -17, -17R engines not incorporating PWA SB No. 5738.
Requirement: 1. Inspect the seventh stage airseal for evidence of corrosion and/or cracking.
2. Action in accordance with PWA SB No. 5738.
Compliance: 1. At next scheduled engine shop visit which requires disassembly of the engine at any flange other than the fan case or thrust reverser, and thereafter at intervals not to exceed 8,000 cycles.
2. (a) For engines with an aircraft fleet annual utilisation of 500 cycles or greater, at next disassembly of the high compressor from the diffuser case.
(b) For engines with an aircraft fleet annual utilisation of less than 500 cycles, at next engine shop visit, but no later than 31 December 1990.
Effective: 22 February 1990.
Background: This Directive has been amended to alleviate the original calendar compliance requirement, and to reflect advice received from the manufacturer. The Directive now requires repetitive inspections of pre SB No. 5738 airseals until incorporation of SB No. 5738.
Overview
The Civil Aviation Regulations 1998, specifically Part 39 - 106, establish a schedule of airworthiness directives to ensure the safety of civil aviation in Australia. One such directive, AD/JT8D/24, pertains to Pratt and Whitney Turbine Engines of the JT8D series. Enacted by the Civil Aviation Safety Authority, this directive aims to address issues related to the seventh stage compressor airseal, particularly those engines that do not incorporate PWA Service Bulletin No. 5738. The policy objective is to mandate regular inspections to detect and rectify any corrosion or cracking, thus preventing potential safety hazards and ensuring compliance with the required maintenance intervals.
This legislative instrument amends the original compliance requirement to reflect updated advice from the manufacturer, mandating repetitive inspections of airseals that do not yet incorporate SB No. 5738. The directive is effective from 22 February 1990, requiring inspections at specific intervals depending on the engine's annual utilisation cycles. This ensures that engines receive the necessary maintenance to maintain airworthiness standards and ultimately protect the safety of all those involved in civil aviation.
Scope and Application
The Civil Aviation Safety Authority Schedule of Airworthiness Directives, specifically AD/JT8D/24 Amendment 1, pertains to Pratt and Whitney turbine engines of the JT8D series, including the models JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -17, and -17R, which do not incorporate PWA Service Bulletin No. 5738. This legislation applies to the inspection of the seventh stage compressor airseal for any signs of corrosion or cracking, as well as mandates actions in accordance with PWA Service Bulletin No. 5738. Compliance with this directive requires inspections at specific engine disassembly intervals and is contingent upon the annual utilisation of the aircraft fleet, with different timelines for fleets with annual utilisations of 500 cycles or more, and less than 500 cycles. The directive is applicable nationally and is enforced under the Civil Aviation Regulations 1998, ensuring safety standards are consistently maintained across the Commonwealth of Australia.
Key Provisions
The Pratt and Whitney Turbine Engines - JT8D Series Airworthiness Directive (AD/JT8D/24Amdt 1) pertains to the seventh stage compressor airseal and applies to JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -17, and -17R engines that do not incorporate PWA SB No. 5738 (section 1). This directive requires the inspection of the seventh stage airseal for evidence of corrosion and/or cracking, and mandates actions in accordance with PWA SB No. 5738 (section 2). The inspections must be conducted at the next scheduled engine shop visit that involves disassembling the engine at any flange other than the fan case or thrust reverser, and should not exceed intervals of 8,000 cycles (section 3.1). For engines with an aircraft fleet annual utilisation of 500 cycles or more, the inspection must occur at the next disassembly of the high compressor from the diffuser case. For engines with an annual utilisation of less than 500 cycles, the inspection must be carried out at the next engine shop visit but no later than 31 December 1990 (section 3.2).
Entities governed by this directive must ensure that the specified inspections are performed at the required intervals and in accordance with the procedures outlined in PWA SB No. 5738. The compliance with this directive is critical for maintaining the airworthiness of Pratt and Whitney JT8D Series engines, and thus, the safety of civil aviation operations. The AD/JT8D/24Amdt 1 mandates that inspections be carried out by qualified personnel who are familiar with the procedures and requirements set forth in the directive and the service bulletin.
Failure to comply with the requirements set forth in this airworthiness directive may result in serious safety concerns, potentially leading to engine failure or other aviation incidents. Although the specific legal consequences of non-compliance are not detailed in the text, it is reasonable to infer that breaches could lead to enforcement actions by the Civil Aviation Safety Authority (CASA), including fines, penalties, and other regulatory sanctions. The exact nature and severity of these consequences would depend on the specific circumstances and the extent of the non-compliance. The directive came into effect on 22 February 1990, and it was amended to reflect advice from the manufacturer and to change the compliance requirement from a calendar-based system to a cycle-based system. This amendment ensures that inspections are conducted more frequently for engines with higher utilisation rates, thereby enhancing safety measures.