COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Pratt and Whitney Turbine Engines - JT9D Series
AD/JT9D/22 First Stage High Pressure Turbine Airseal 2/91
Applicability: JT9D-3A, -7, -7A, -7A(SP), -7AH, -7F, -7H, -7J, -20, -20J engines fitted with P/N 797576, 797576P48, 793707 first stage high pressure turbine airseals.
Requirement: 1. Replace first stage high pressure turbine airseals as listed by serial number in PWA Service Bulletin No 5873 Rev 1, Para 2, Part A.
2. Inspect, first stage high pressure turbine airseals not listed by serial number in PWA Service Bulletin No 5873 Rev 1, Para 2, Part A, in accordance with PWA Service Bulletin No 5873 Rev 1, Para 2, Part B.
Note: FAA AD 90-23-19 refers.
Compliance: 1. At next engine shop visit regardless of planned maintenance action or reason for engine removal.
2. At next access to affected parts.
Background: This Directive reflects advice of an uncontained JT9D-7R4H1 engine failure event.
The failure was attributed to cracking of an Inconel-718 material airseal. Certain lower rated JT9D models may also be fitted with the same part number airseal. This Directive requires replacement or inspection of those airseals.
Overview
The Civil Aviation Regulations 1998, specifically PART 39 - 106, addresses the safety and operational standards of civil aviation in Australia. Enacted by the Commonwealth of Australia, these regulations are administered by the Civil Aviation Safety Authority (CASA) to ensure the safe, efficient, and orderly development of civil aviation. The regulations were introduced to fill a critical gap in ensuring airworthiness and safety standards across the aviation industry, particularly in light of incidents like the uncontained engine failure event of a JT9D-7R4H1 engine. The policy objective behind these regulations is to mandate strict safety measures and compliance with airworthiness directives to prevent potential hazards and ensure the highest standards of safety for passengers and crew.
One specific directive, AD/JT9D/22, targets Pratt and Whitney Turbine Engines - JT9D Series, focusing on the first stage high pressure turbine airseals. This directive was issued following an uncontained engine failure event attributed to the cracking of an Inconel-718 material airseal. The directive mandates the replacement or inspection of specified airseals to mitigate the risk of similar incidents. Compliance with this directive is required at the next engine shop visit or access to the affected parts, reflecting the urgency and importance of addressing potential safety hazards in aviation.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 106 concerning Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to Pratt and Whitney JT9D Series turbine engines, including models JT9D-3A, -7, -7A, -7A(SP), -7AH, -7F, -7H, -7J, -20, and -20J that are fitted with particular first stage high pressure turbine airseals identified by specific part numbers. This legislation mandates the replacement or inspection of the specified airseals to ensure airworthiness and safety in line with the PWA Service Bulletin No 5873 Rev 1. The requirement to comply with these directives must be met at the next engine shop visit or whenever the affected parts are accessible, regardless of the reason for the engine's removal. This regulatory measure reflects a response to an uncontained engine failure event, highlighting the critical importance of maintaining airworthiness standards across the specified engine models.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39, includes an Airworthiness Directive (AD) pertaining to Pratt and Whitney JT9D series turbine engines, identified as AD/JT9D/22. This directive concerns the first stage high-pressure turbine airseal (sections 1 and 2). The AD applies to JT9D-3A, -7, -7A, -7A(SP), -7AH, -7F, -7H, -7J, -20, -20J engines fitted with particular serial number airseals (section 3). The main requirements include replacing certain airseals as specified in PWA Service Bulletin No 5873 Rev 1, Para 2, Part A, and inspecting other airseals according to the same bulletin's Para 2, Part B (section 4).
The AD imposes specific obligations on the parties involved. Operators and maintenance providers must replace the listed airseals at the next engine shop visit, regardless of the reason for engine removal or any planned maintenance actions (section 5). For airseals not listed, inspections must be conducted at the next access to the affected parts (section 6). This directive follows an uncontained engine failure event attributed to airseal cracking, necessitating strict compliance to ensure airworthiness and safety (section 7).
Failure to comply with the requirements of this AD can result in significant legal and safety consequences. The AD references FAA AD 90-23-19, indicating that non-compliance might be treated similarly to violations under the Federal Aviation Administration's regulations (section 8). While the exact penalties are not specified in this text, typically, non-compliance with ADs can lead to enforcement actions, fines, and potential grounding of aircraft. The severity of the penalties reflects the critical nature of the airseal issues highlighted by the AD (section 9).