AD/A320/88 - Wing Front Spar Vertical Stringers

Overview

The Civil Aviation Regulations 1998, specifically PART 39 - 105, addresses the safety concerns associated with Airbus Industrie A319, A320, and A321 series aeroplanes. Enacted by the Parliament of the Commonwealth of Australia, this regulation was introduced to ensure the safety of air travel by addressing potential structural issues in these aircraft models. The Civil Aviation Safety Authority issued this directive to mandate specific inspections and maintenance procedures to mitigate the risk of undetected cracks in the wing front spar vertical stringers, which could compromise the structural integrity of the aircraft. The directive aims to ensure that any potential issues are identified and rectified before they pose a risk to flight safety. This legislation was enacted in response to findings from full-scale fatigue tests that revealed bending cracks on the front spar vertical stringers at Frame 36. The objective is to ensure that these aircraft maintain their airworthiness by requiring regular inspections and timely corrective actions. Compliance with these directives is essential to prevent the propagation of cracks, which could lead to significant structural damage and potential safety hazards. The regulations set specific intervals for inspections and actions to be taken based on the findings, ensuring that any issues are addressed promptly and effectively.

Scope and Application

The Civil Aviation Regulations 1998, under Part 39 - 105, specifically Airworthiness Directives, governs the safety and airworthiness of Airbus Industrie A319, A320, and A321 series aeroplanes, with AD/A320/88 focusing on the wing front spar vertical stringers. This legislation applies to all A320 models that have not incorporated Modification 21290 or Service Bulletin A320-57-1017. The directive mandates an eddy current inspection at the top end of the front spar vertical stringers at frame 36, in line with the instructions in Airbus Industrie Service Bulletin A320-57-1016. If cracks are found, further inspections or manufacturer consultations are required, based on the synoptic chart in the bulletin. If no cracks are detected, the inspection must still be repeated. Compliance requires the inspection before the accumulation of 24,000 flights and at intervals not exceeding 4,000 or 14,000 flights, as outlined in the directive. This directive, effective from 29 January 1998, responds to fatigue test findings of bending cracks at Frame 36, ensuring the safety of in-service aircraft by preventing the propagation of undetected cracks.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, under the Civil Aviation Safety Authority Schedule of Airworthiness Directives, includes detailed provisions for the maintenance and inspection of Airbus Industrie A319, A320, and A321 series aeroplanes. The AD/A320/88 directive focuses on the wing front spar vertical stringers (section 2/98). According to this directive, operators must conduct an eddy current inspection at the top end of the front spar vertical stringers at frame 36 in accordance with Airbus Industrie Service Bulletin A320-57-1016. If cracks are detected, further actions as outlined in the Service Bulletin's accomplishment instructions are required, potentially necessitating contact with the manufacturer. If no cracks are detected, the inspection must still be repeated at specific intervals. Operators of A320 models without Modification 21290 or Service Bulletin A320-57-1017 incorporated must comply with the airworthiness directive's stringent timelines. The inspection must be completed before the aircraft accumulates 24,000 flights. Additionally, it must occur before the next flight or at intervals not exceeding 4,000 flights, as determined by the Service Bulletin's chart. Further inspections must be conducted at intervals not exceeding 14,000 flights. Compliance with these requirements is essential to ensure the continued airworthiness of the aircraft. The directive became effective on 29 January 1998, following full-scale fatigue tests that revealed bending cracks at the front spar vertical stringer at Frame 36. The background of the directive highlights the potential for undetected cracks to propagate and form long cracks in the top end of the front spar vertical stringers, which poses a significant risk to the safety of in-service aircraft. Failure to comply with these airworthiness directives can result in severe consequences. Non-compliance may lead to grounding of the aircraft until the required inspections and repairs are completed, potentially causing significant operational disruptions. Furthermore, regulatory authorities may impose fines and penalties, and in more severe cases, criminal charges could be brought against operators or responsible individuals. The exact penalties are determined by the Civil Aviation Safety Authority and can vary based on the severity and frequency of the breaches.