AD/SF340/64 - Landing Gear Electrical Relay 15GA

Overview

The Civil Aviation Regulations 1998, specifically within Part 39, includes a series of airworthiness directives to ensure the safety and airworthiness of aircraft. One such directive, AD/SF340/64, pertains to the SAAB SF340 series aeroplanes, particularly those with serial numbers ranging from 380 to 499. This directive was enacted to address the problem of landing gear control circuit breaker 7GA opening, which can lead to the landing gear not being locked down due to a short-circuit in relay 15GA. The policy objective is to maintain the highest safety standards in civil aviation by mandating specific maintenance actions, including inspecting and replacing parts, and conducting tests to ensure the operational integrity of the aircraft. The directive was issued by the Civil Aviation Safety Authority and became effective on 18 June 1998.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the airworthiness of aircraft within Australia, extending to SAAB SF340 series aeroplanes. This legislative instrument mandates that SAAB 340B series aeroplanes with serial numbers ranging from 380 to 499 inclusive must comply with certain maintenance and inspection requirements to ensure airworthiness. The directive requires the inspection and, where necessary, the replacement of specific components such as relay 15GA, its socket, and related wiring harness, alongside other tests and operational checks as stipulated in SAAB Aircraft AB Service Bulletin SAAB 340-32-115 dated 7 April 1998. This directive aims to address a safety concern related to potential landing gear malfunctions, which could lead to significant risks during landing operations. Compliance must be achieved within 400 hours of time in service from the directive’s effective date of 18 June 1998. This regulation underscores the importance of stringent safety measures within the aviation industry to ensure the reliability and safety of aircraft operations within Australian jurisdiction.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105 under the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, mandates certain actions for the SAAB 340B series aeroplanes with serial numbers 380 through 499. This directive, identified as AD/SF340/64, was issued on 7 April 1998 and became effective on 18 June 1998. It pertains to a specific issue identified with the landing gear electrical relay 15GA and requires compliance within 400 hours of time in service from the directive's effective date. The directive references SAAB Aircraft AB Service Bulletin SAAB 340-32-115, which outlines the necessary actions to rectify the identified issues. The directive requires the inspection and potential replacement of relay 15GA, the relay socket, and related wiring harness. It also mandates changing the nut-plate in the flight deck floor, conducting a flight idle stop solenoid test, performing a functional test of the active noise system, and carrying out an operational test of the fluorescent lamps. The directive references LFV AD 1-125 as additional guidance in ensuring compliance. The primary motivation behind these requirements stems from reports of the landing gear control circuit breaker 7GA opening, preventing normal landing gear extension and potentially leading to the landing gear not being locked down. Investigation revealed that a short-circuit in relay 15GA, likely caused by fluid leaking through carpet attachment holes on the cockpit floor and contaminating the relay, is the root cause. Compliance with this directive is mandatory for all relevant SAAB 340B series aeroplanes, and failure to adhere to the specified actions and timeline could result in serious safety implications. Operators of these aircraft must ensure that the required inspections and actions are performed by certified personnel within the stipulated timeframe to maintain the airworthiness of the aircraft. Non-compliance with the directive could lead to potential grounding of the aircraft until the necessary actions are completed and approved by CASA. Breach of the provisions outlined in this airworthiness directive may result in serious consequences. The Swedish airworthiness authority, and by extension CASA, takes such directives very seriously due to their direct impact on the safety of aviation. Penalties for non-compliance could include fines, operational restrictions, or even the suspension of the aircraft's airworthiness certificate. Operators found in breach of this directive may face significant civil or criminal penalties, depending on the severity and impact of the non-compliance. In extreme cases, this could lead to criminal charges and imprisonment for responsible individuals or entities.