Overview

The Airworthiness Directive (AD) AD/JT15D/9, issued by the Civil Aviation Safety Authority (CASA) in 2003, targets an identified safety concern regarding Pratt and Whitney Canada (PWC) JT15D series turbine engines. Specifically, the AD addresses the problem of impeller fractures that have led to uncontained liberation of high-energy fragments, a risk exacerbated by machining marks on the impeller rear face. This directive was introduced to mitigate these risks by requiring a borescope inspection and necessary repairs or replacements of affected impellers, thereby ensuring continued airworthiness and safety of the specified aircraft engines. The policy objective is to prevent potential in-flight failures that could compromise safety, as evidenced by the CASA delegate’s requirement for inspections and necessary actions to be carried out in a timely manner.

Scope and Application

The Airworthiness Directive (AD) F2006B10971 applies to Pratt and Whitney Canada (PWC) JT15D-1, JT15D-1A, and JT15D-1B engines that incorporate impeller Part Number (P/N) 3020365. Specifically, it targets engines that have not been inspected according to Overhaul Manual Revision 14 or later, as well as those with serial numbers not listed in Table 1 of PWC Service Bulletin (S/B) 7590. The AD mandates a borescope inspection of the impeller in accordance with PWC S/B 7590 dated 23 May 2003, and requires any non-compliant impellers to be repaired or replaced before further flight. Compliance must be achieved either at the next engine shop visit or within 250 flight cycles for engines with impellers having a Total Cycles Since New (TCSN) of 5000 or more flight cycles, whichever comes first. This directive extends across the Commonwealth of Australia and is enforceable by the Civil Aviation Safety Authority (CASA). The AD became effective on 2 October 2003 and was gazetted on 10 September 2003.

Key Provisions

The Airworthiness Directive (AD) AD/JT15D/9 issued by the Civil Aviation Safety Authority (CASA) under subregulation 39.1(1) of the Civil Aviation Safety Regulations 1998 (CASR) applies to Pratt and Whitney Canada (PWC) JT15D-1, JT15D-1A, and JT15D-1B engines that incorporate impeller Part Number (P/N) 3020365. The AD requires specific actions to be taken in order to address an unsafe condition related to the impeller rear face. Specifically, if an engine has not been inspected as per Overhaul Manual Revision 14 or later, or if the engine's Serial Number (S/N) is not listed in Table 1 of PWC Service Bulletin (S/B) 7590, the AD mandates that an inspection be conducted in accordance with PWC S/B 7590 dated 23 May 2003. Furthermore, any impellers that do not meet the inspection requirements must be repaired or replaced prior to further flight. The AD imposes certain obligations on the parties or entities it governs. The primary requirement is to perform an inspection of the impeller according to PWC S/B 7590 dated 23 May 2003. This inspection must occur either at the next engine shop visit or within 250 flight cycles for engines that have impellers with a Total Cycles Since New (TCSN) of 5000 or more flight cycles, whichever comes first. If any impellers do not meet the inspection requirements, they must be repaired or replaced before any further flight. These obligations aim to ensure that the unsafe condition related to impeller fractures and uncontained liberation of high energy fragments is addressed. Failure to comply with the requirements set out in this AD may result in civil or criminal consequences. While specific penalties are not stated in the text, the AD highlights that non-compliance with airworthiness directives issued by CASA can result in enforcement actions. These actions may include fines, suspension or revocation of airworthiness certificates, or other regulatory measures. It is important for the governed parties to adhere to the AD in order to maintain the airworthiness of the aircraft and ensure the safety of the aviation industry.