AD/CESSNA 177/33 - Upper Shoulder Harness Adjuster Spring

Overview

The Airworthiness Directive issued under the Civil Aviation (Airworthiness of Aircraft) Regulations 1998 addresses an identified safety issue with the upper shoulder harness adjusters on certain Cessna 177 Series aeroplanes. The Civil Aviation Safety Authority (CASA) issued this directive to ensure the safety of pilots and passengers by preventing potential slippage of the shoulder harness. This slippage could compromise the harness's ability to maintain proper belt length adjustment and tension, potentially leading to serious safety risks. The directive applies to Models 177, 177A, and 177B aircraft with specific serial numbers. Compliance with the directive is required within 25 hours of time in service or at the next annual inspection after 23 December 2004, whichever comes first. The policy objective is to mitigate the risk of unsafe conditions that could arise from the inadvertent installation of a small wire spring in the shoulder harness adjusters.

Scope and Application

This Airworthiness Directive applies to the specific models of Cessna 177, 177A, and 177B aircraft, identified by serial numbers listed in the Cessna Single Engine Service Bulletin SEB86-8 Revision 1, dated 28 July 2003. The purpose of this AD is to address an identified safety issue with the upper shoulder harness adjusters, specifically the presence of a retainer spring that could potentially lead to harness slippage during flight, thus compromising safety. The directive mandates inspection and specific actions to be taken by the aircraft operator, including removal or marking of the retainer spring and logging compliance. Compliance with the AD must be achieved within 25 hours of the directive's effective date or during the next annual inspection, whichever comes first. This directive, issued under the Civil Aviation Safety Authority (CASA), has a national jurisdictional reach within Australia and becomes effective on 23 December 2004, as gazetted on 1 December 2004.

Key Provisions

The Airworthiness Directive (AD) in question, AD/CESSNA 177/33, applies specifically to Cessna 177, 177A, and 177B series aircraft with serial numbers listed in Cessna Single Engine Service Bulletin SEB86-8 Revision 1, dated 28 July 2003. The directive requires an inspection of the upper shoulder harness adjuster, part number 443030-401, to determine the presence of a retainer spring (section 1). If the retainer spring is found, it must be removed and the identification number stamped out before further flight (section 1). If the retainer spring is not found, an entry must be made in the aircraft logbook to indicate compliance with the directive (section 1). Additionally, the directive mandates the incorporation of only those Cessna Accessory Kits that have been identified, inspected, and modified in accordance with the requirement document (section 2). Compliance with the Service Bulletin SEB86-8 original issue, dated 21 November 1986, is considered terminating action for the requirements of this directive if the shoulder harness adjuster part number 443030-401 was used (section 2). The obligations under this AD involve conducting the specified inspections and making entries in the aircraft logbook. Owners and operators of the affected aircraft must ensure that the upper shoulder harness adjuster is inspected for the presence of the retainer spring and that any necessary actions are taken to remove the spring or record compliance in the logbook. Additionally, they must ensure that only approved accessory kits are used and that these kits have been inspected and modified as required. The directive further obligates the operators to ensure that these actions are completed within the stipulated timeframes, either within 25 hours of time in service or at the next annual inspection after 23 December 2004, whichever occurs first (section 1). Failure to comply with this Airworthiness Directive can result in serious safety issues, particularly the risk of the shoulder harness failing to maintain proper adjustment and tension, which could lead to significant operational hazards. However, the AD does not explicitly outline specific penalties for non-compliance. Nonetheless, non-compliance with ADs is generally treated seriously by the Civil Aviation Safety Authority (CASA) and can lead to enforcement actions, including the potential for CASA to direct the grounding of the aircraft until compliance is achieved. Additionally, in severe cases, non-compliance could result in civil or criminal liability under other relevant aviation regulations or general aviation safety laws, although such outcomes are not explicitly detailed in this specific AD.