COMMONWEALTH OF AUSTRALIA (Civil Aviation Safety Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
Boeing 737 Series Aeroplanes
AD/B737/225 Proximity Switch Electronics Unit 6/2004
Applicability: Model 737-600, -700, -700C, -800, and -900 series aeroplanes, as listed in Boeing Alert Service Bulletin (ASB) 737-32A1343 dated 26 July 2001.
Requirement: 1. Remove Proximity Switch Electronics Unit (PSEU) part number (P/N) 285A1600-2 or 285A1600-3 and replace it with a PSEU P/N 285A1600-4, in accordance with the Accomplishment Instructions of ASB 737-32A1343.
2. PSEU P/N 285A1600-2 or 285A1600-3 may not be installed on any aeroplane as a replacement part.
Note: FAA AD 2004-07-10 Amdt 39-13554 refers.
Compliance: For Requirement 1 - Within 18 months after the effective date of this Directive.
For Requirement 2 - As of the effective date of this Directive. This Airworthiness Directive becomes effective on 10 June 2004.
Background: This Directive requires replacement of the PSEU with a new, improved unit. This action is necessary to prevent a malfunction of the aural warning for the landing gear, leading the crew to open the circuit breaker for the aural warning horn which stops the operation of other aural warnings of malfunctions in other systems and, thus, could jeopardize a safe flight and landing.
James Coyne
Delegate of the Civil Aviation Safety Authority 27 April 2004
The above AD is notified in the Commonwealth of Australia Gazette on 19 May 2004.
Overview
The Civil Aviation Safety Regulations 1998, as amended, provide the legislative framework for ensuring the safety of civil aviation in Australia. One particular Airworthiness Directive, issued by the Civil Aviation Safety Authority (CASA) in 2004, addresses a safety concern regarding the Proximity Switch Electronics Unit (PSEU) in Boeing 737 Series Aeroplanes. The AD was enacted to rectify an issue where the PSEU could lead to a malfunction of the aural warning for the landing gear, potentially causing the flight crew to disable other critical aural warnings. This could have serious implications for flight safety, prompting CASA to mandate the replacement of the PSEU with an improved version to prevent such malfunctions and ensure safe flight operations.
Scope and Application
The Civil Aviation Safety Regulations 1998 (CASR 1998) under the authority of the Civil Aviation Safety Authority (CASA) sets forth regulations that apply to all aircraft and aeronautical products within the Commonwealth of Australia. Specifically, Airworthiness Directive (AD) AD/B737/225 pertains to the Boeing 737 series aeroplanes, including models 737-600, -700, -700C, -800, and -900. This AD mandates that the Proximity Switch Electronics Unit (PSEU) part numbers 285A1600-2 or 285A1600-3 be removed and replaced with PSEU part number 285A1600-4. This replacement is necessary to address a safety concern where the existing PSEUs could malfunction and cause the crew to disable critical aural warnings, thus compromising flight safety. This AD applies immediately for the prohibition of installing the older PSEUs and within 18 months for the replacement of the PSEUs with the specified new part. The directive's scope is explicitly limited to the mentioned Boeing 737 series aeroplanes, ensuring that these aircraft maintain the required safety standards.
Key Provisions
The Civil Aviation Safety Regulations 1998, Part 39, specifically Airworthiness Directive AD/B737/225, mandates particular actions concerning the Boeing 737 Series Aeroplanes, particularly the Proximity Switch Electronics Unit (PSEU). The directive applies to Model 737-600, -700, -700C, -800, and -900 series aeroplanes listed in Boeing Alert Service Bulletin (ASB) 737-32A1343 dated 26 July 2001. The AD requires the removal and replacement of PSEU part numbers 285A1600-2 or 285A1600-3 with a PSEU P/N 285A1600-4, in line with the Accomplishment Instructions of ASB 737-32A1343. Additionally, PSEU P/N 285A1600-2 or 285A1600-3 must not be installed as a replacement part on any aeroplane.
Under the Civil Aviation Safety Regulations, the primary obligations imposed on the parties governed by this directive include the timely removal and replacement of the specified PSEU parts. Specifically, Requirement 1 must be completed within 18 months from the effective date of the directive, while Requirement 2 must be fulfilled immediately upon the directive's effective date. The purpose of these obligations is to prevent a malfunction of the aural warning for the landing gear, which could lead to the crew disabling the circuit breaker for the aural warning horn, thereby halting other critical aural warnings and potentially compromising flight safety.
Failure to comply with the requirements of this Airworthiness Directive may result in serious safety issues. The regulations do not explicitly detail the specific penalties or legal consequences for non-compliance; however, it is understood that non-compliance with Airworthiness Directives can lead to severe repercussions, including potential enforcement actions by the Civil Aviation Safety Authority. These actions might encompass fines, operational restrictions, or even grounding of the aircraft until compliance is achieved. The exact penalties would depend on the severity of the non-compliance and the specific circumstances involved.