AD/PC-12/22 - Electrical Power - Suppression Filters

Overview

The Civil Aviation Regulations 1998, specifically the Airworthiness Directive AD/PC-12/22 issued in 1999, addresses a safety issue with the Pilatus PC-12 Series aeroplanes. This legislative instrument, enacted by the Commonwealth of Australia, aims to rectify a problem identified in the electrical power suppression filters of certain models, specifically those with Manufacturers Serial Numbers (MSN) ranging from 101 to 289. The directive requires the removal and replacement of a specific part, the suppression filter (A250) part number 524.52.12.358, with a new part number 524.52.12.502, to prevent potential short circuits and subsequent overheating of electrical wiring. Compliance with the directive is mandated within ten flights post the directive's effective date and before further flights after the initial compliance. The policy objective of this directive, as enforced by the Civil Aviation Safety Authority, is to enhance the safety of the Pilatus PC-12 Series aeroplanes by addressing electrical system vulnerabilities. This directive ensures that the aircraft meet the necessary safety standards to prevent electrical failures that could compromise flight safety. By specifying the required changes and compliance timelines, the directive provides a clear framework for maintaining the airworthiness of affected aircraft.

Scope and Application

The Civil Aviation Safety Authority's Airworthiness Directive (AD) AD/PC-12/22 pertains to the Pilatus PC-12 series aeroplanes, specifically those with Manufacturers Serial Numbers (MSN) ranging from 101 to 289, inclusive. This directive mandates the removal of the existing suppression filter (A250) part number (P/N) 524.52.12.358 and its replacement with a new suppression filter (A250) P/N 524.52.12.502, as outlined in Pilatus PC-12 Service Bulletin (SB) No.24-014 dated 27 October 1999. The directive requires compliance within the next ten flights following its effective date of 8 November 1999 and before further flight post-installation. The installation of the new suppression filter should be verifiable by its part number and a black placard with a yellow A250 marking. Additionally, system tests must be conducted as per paragraph 3(D) of the aforementioned service bulletin. Failure to adhere to these directives could result in operational hazards, as highlighted by the malfunction of circuit breaker CB 235 following the installation of the previous service bulletin, SB 24-012. This AD ensures the continued safe operation of the specified Pilatus PC-12 aircraft by mitigating the risk of electrical failures and potential overheating damage.

Key Provisions

The Civil Aviation Regulations 1998, particularly Part 39 - 105, includes the Civil Aviation Safety Authority Schedule of Airworthiness Directives, which is instrumental in ensuring the safety and airworthiness of aircraft in Australia. Specifically, AD/PC-12/22 pertains to the Pilatus PC-12 Series Aeroplanes, focusing on electrical power suppression filters. Section 13/99 outlines the applicability of this directive to all Model PC-12 and PC-12/45 aeroplanes with Manufacturers Serial Numbers (MSN) from 101 to 289. The directive mandates two primary requirements, beginning with the removal of the existing suppression filter (A250) part number (P/N) 524.52.12.358 and its replacement with a new suppression filter (A250) P/N 524.52.12.502. This replacement must be carried out in accordance with Pilatus PC-12 Service Bulletin No. 24-014 dated 27 October 1999. The new filter should be identifiable by its part number and a black placard marked with a yellow A250. Compliance with AD/PC-12/22 involves a system test after the installation of the new suppression filter. This test must be performed as detailed in paragraph 3(D) of Pilatus PC-12 Service Bulletin No. 24-014. The directive also references FOCA Switzerland AD HB 99-542 for additional context. The directive specifies two compliance phases: the first requires action within the next ten flights after the directive's effective date, and the second necessitates the system test before any further flight after the initial requirement is met. The directive becomes effective on 8 November 1999. Operators and owners of Pilatus PC-12 Series Aeroplanes must adhere to these requirements to ensure compliance with the Civil Aviation Regulations. Failure to comply with AD/PC-12/22 may result in the aircraft being deemed unairworthy. Consequently, non-compliance could lead to civil or criminal penalties, including fines and potential imprisonment. The exact penalties may vary based on the severity and circumstances of the breach, but the regulations allow for significant enforcement actions to ensure the safety and airworthiness standards are upheld. The Australian Civil Aviation Safety Authority (CASA) may impose penalties under Section 94 of the Civil Aviation Act 1988, which can include substantial fines and imprisonment for serious violations.