Overview

The Civil Aviation Safety Regulations 1998 (CASR) were enacted by the Parliament of Australia to ensure the safety of civil aviation within the country. This legislation provides a framework for the regulation of airworthiness, licensing, and other safety aspects of civil aviation. Specifically, Part 39 - 105 Civil Aviation Safety Authority Schedule of Airworthiness Directives within the CASR addresses the issuance of directives by the Civil Aviation Safety Authority (CASA) to correct unsafe conditions on aircraft. This particular Airworthiness Directive (AD) for Cessna 120 and 140 Series Aeroplanes, issued on 15 May 2003, aims to address issues related to the wing drag wire system. The policy objective of the AD is to ensure the continued airworthiness of these aircraft by mandating regular inspections and necessary repairs to prevent potential safety hazards. The directive requires inspections and specific actions to be taken within a defined timeframe to maintain compliance with safety standards.

Scope and Application

The Civil Aviation Safety Regulations 1998, specifically Part 39 - 105, under the Civil Aviation Safety Authority (CASA) mandate, applies to all Model 120 and 140 aircraft operating within the Australian jurisdiction. This Airworthiness Directive (AD) issued by a CASA delegate requires specific actions concerning the wing drag wire system to ensure compliance with safety standards. The directive mandates that inspections must be conducted for loose or broken drag wires and any damage to the ribs. It is imperative to install inspection openings aft of the rear spar if they are not already present. Post-inspection, any loose drag wires must be re-rigged, broken drag wires replaced, and damaged ribs repaired or replaced as necessary. The directive also specifies the replacement of broken No. 6 drag wires in the outer wing panel with No. 8 drag wires. While buckling of the intermediate rib flanges at the spar cutouts does not render the wing unserviceable, reinforcement is recommended if the flanges are cracked. The AD must be adhered to within 100 hours of time in service or within 12 months from 15 May 2003, whichever comes first, and subsequently at intervals not exceeding 100 hours of service. This directive, effective from 15 May 2003, ensures that all operations comply with stringent safety protocols, maintaining the airworthiness of the specified aircraft within Australian airspace.

Key Provisions

The main operative sections of the Airworthiness Directive (AD) AD/CESSNA 120/9 pertain to the inspection, maintenance, and repair of the wing drag wire system for all Cessna 120 and 140 series aircraft. Specifically, section (a) mandates that all Model 120 and 140 aircraft must undergo an inspection to check for loose or broken drag wires and for any damage to the ribs (section 1). Section (b) requires the installation of inspection openings aft of the rear spar, just inboard of Rib 5 and just outboard of Rib 10, if such openings are not already present (section 2). Following the inspection, it is necessary to re-rig any loose drag wires, replace broken ones, and repair or replace any buckled drag ribs as needed (section 3). Moreover, broken No. 6 drag wires in the outer wing panel must be replaced with No. 8 drag wires (section 4). The AD also recommends reinforcement with Cessna part number 10004-58 if the intermediate rib flanges at the spar cutouts are buckled, and mandates this reinforcement if the flanges are cracked (section 5). The obligations and requirements imposed by this AD on the aircraft operators and owners include ensuring that the specified inspections and repairs are carried out meticulously. The compliance period is defined as either within 100 hours of time in service or 12 months after 15 May 2003, whichever occurs first, and subsequently, the inspections and repairs must be carried out at intervals not exceeding 100 hours of time in service (section 6). The AD underscores the necessity of following the outlined procedures and using the specified parts for repairs to maintain the airworthiness of the aircraft. Compliance with these directives is critical to ensure the safety and operational integrity of the Cessna 120 and 140 series aircraft. The Civil Aviation Safety Regulations 1998 establish clear consequences for non-compliance with Airworthiness Directives. Any breach of the requirements outlined in this AD may result in severe civil or criminal penalties. These could include fines and potential prosecution for violations that compromise the safety of the aircraft. The maximum penalties are determined by the specific breach and the regulatory framework under which the AD is issued. Operators who fail to adhere to the AD may face significant financial penalties and legal actions that could lead to the grounding of non-compliant aircraft. Ensuring strict adherence to these directives is therefore imperative to avoid such legal repercussions.