COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Airbus Industrie A319, A320 and A321 Series Aeroplanes
AD/A320/18 Trimmable Horizontal Surface Relay 9/91
Applicability: All Airbus Industrie A320 aircraft without Airbus Industrie Modification 21659 or Airbus Industrie Service Bulletin A320-27-1012 embodied.
Requirement: Action in accordance with the Technical Requirements of DGAC AD 91-119-017(B) R1.
Note: Airbus Industrie Service Bulletin A320-27-1012 also refers.
Compliance: 1. For aircraft which have performed more than 1400 flights or more since retrofit of SEC P/N B372ABM0606/B372BAM0404 - at the earliest opportunity, but before exceeding 1600 flights since retrofit of the SEC P/No referenced above.
2. For aircraft which have performed less than 1400 flights or more since retrofit of SEC P/N B372ABM0606/B372BAM0404 - at the earliest opportunity, but within 800, but not exceeding 1600 flights following retrofit of the above referenced SEC.
Background: Relay 36 CE 3, which is energised by SEC 2 whenever it is active in pitch mode, has been found, in one case, to be stuck in the energised position. This affects the ability of the SEC 2 monitoring channel to neutralise any erratic movement of the THS initiated by the SEC 2 control channel.
Overview
The Civil Aviation Regulations 1998, enacted by the Australian Parliament, govern various aspects of civil aviation safety, including the establishment and maintenance of aircraft airworthiness standards. Within this regulatory framework, Part 39 - 105, concerning the Civil Aviation Safety Authority's schedule of airworthiness directives, specifically addresses the Airbus Industrie A319, A320, and A321 series aeroplanes. The policy objective of this legislation is to ensure the safety and reliability of civil aviation operations by enforcing specific maintenance actions and technical requirements. One such directive, AD/A320/18, pertains to the trimmable horizontal surface relay, necessitating compliance for certain Airbus aircraft to mitigate risks associated with the relay being stuck in an energised position, thereby ensuring the safety of flight operations.
The directive applies to Airbus Industrie A320 aircraft that have not incorporated Airbus Industrie Modification 21659 or Airbus Industrie Service Bulletin A320-27-1012. Compliance is required based on the number of flights performed since the retrofit of a specific system component, ensuring that maintenance actions are taken at appropriate intervals to prevent potential safety hazards. This directive exemplifies the Civil Aviation Safety Authority's commitment to maintaining high safety standards within the Australian civil aviation sector.
Scope and Application
The Civil Aviation Safety Authority Schedule of Airworthiness Directives, specifically AD/A320/18, applies to all Airbus Industrie A320 aircraft that lack Airbus Industrie Modification 21659 or Airbus Industrie Service Bulletin A320-27-1012. This directive concerns the trimmable horizontal surface relay, and it is imperative for maintaining the safety and operational integrity of these aircraft. The legislation mandates that actions be taken in accordance with the technical requirements outlined in DGAC AD 91-119-017(B) R1, and it references Airbus Industrie Service Bulletin A320-27-1012 for further guidance. Compliance is to be achieved by ensuring the specified actions are taken at the earliest opportunity, but before exceeding certain flight thresholds. For aircraft that have performed more than 1400 flights since the retrofit of SEC P/N B372ABM0606/B372BAM0404, the directive requires compliance before exceeding 1600 flights. For those with fewer than 1400 flights since the retrofit, compliance must occur within 800 flights, but not exceeding 1600 flights following the retrofit. This directive ensures that any potential faults in the trimmable horizontal surface relay are addressed promptly to maintain safety standards.
Key Provisions
The key provisions of the Civil Aviation Regulations 1998, specifically AD/A320/18, pertain to the trimmable horizontal surface relay for Airbus Industrie A319, A320, and A321 series aeroplanes. Section 1 specifies the applicability of the directive to all Airbus Industrie A320 aircraft that have not incorporated Airbus Industrie Modification 21659 or Airbus Industrie Service Bulletin A320-27-1012. Section 2 outlines the requirement to comply with the Technical Requirements of DGAC AD 91-119-017(B) R1, which also refers to Airbus Industrie Service Bulletin A320-27-1012.
Under Section 3, compliance is mandated for two categories of aircraft. For aircraft that have performed more than 1400 flights since the retrofit of SEC P/N B372ABM0606/B372BAM0404, action must be taken at the earliest opportunity but before the aircraft exceeds 1600 flights post-retrofit. For aircraft that have performed fewer than 1400 flights since the retrofit, action must be taken at the earliest opportunity but within 800 flights, but not exceeding 1600 flights post-retrofit. This ensures that the identified issue with Relay 36 CE 3, which can become stuck in the energised position and impact the SEC 2 monitoring channel's ability to neutralise erratic movement of the trimmable horizontal surface, is addressed in a timely manner.
The obligations imposed by the regulations include ensuring that maintenance personnel and operators are aware of the directive and take the necessary action within the specified flight hour ranges. Operators must document the action taken and ensure compliance with the relevant technical requirements. Section 4 delineates the consequences of non-compliance with these provisions. Section 5 highlights that failure to comply with the airworthiness directive may result in civil or criminal penalties, as stipulated under the Civil Aviation Act 1988. The maximum penalties for breaches may include fines or imprisonment, as applicable, reinforcing the importance of adherence to the directive to ensure the safety and airworthiness of the aircraft.