AD/CESSNA 400/98 - Horizontal Stabiliser Fwd Attach Bulkhead

Overview

The Civil Aviation Regulations 1998 (the Regulations) were enacted to ensure the safety of civil aviation in Australia, and they are administered by the Civil Aviation Safety Authority (CASA). One specific legislative instrument, AD/CESSNA 400/98, was introduced to address the problem of reported instances of cracking in the horizontal stabiliser attach bulkhead of certain Cessna 400 Series Aeroplanes. This Airworthiness Directive aims to enhance aviation safety by requiring inspections and adjustments to the horizontal stabiliser forward attach bulkhead to mitigate the risk of cracks and fretting. The policy objective is to ensure that these inspections and adjustments are carried out in a timely manner to prevent potential safety hazards. The instrument applies to Model 441 Cessna aeroplanes with specific serial numbers and time in service exceeding 3000 hours. It mandates inspections in accordance with Cessna Service Bulletin CQB91-1 Revision 1 and requires adjustments if Service Kit SK 441-103 has been installed. Compliance with these directives is crucial to maintaining the structural integrity of the aircraft and ensuring the safety of all persons on board.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, applies to the Cessna 400 Series aeroplanes, more precisely to Model 441 serial numbers ranging from 441-001 through 441-0362 that have accrued over 3000 hours of time in service. The regulation is part of the broader legislative framework overseen by the Civil Aviation Safety Authority and is applicable across the Commonwealth of Australia, ensuring a uniform standard of safety and compliance throughout the nation. The primary requirement under this directive mandates an inspection of the horizontal stabiliser forward attach bulkhead for any signs of cracks or fretting, in accordance with the specified Cessna Service Bulletin CQB91-1 Revision 1. If Service Kit SK 441-103 has been installed, additional steps must be taken to inspect and adjust the gap between the F.S.404.145 bulkhead and the horizontal stabiliser aft attach points, following the Accomplishment Instructions of SK 441-103A. Compliance with these regulations must be achieved within specific timeframes, either within 200 hours of service, during the next removal of the horizontal stabiliser, or before 30 April 1993, whichever is earliest, and then at intervals not exceeding 2000 hours until the Service Kit SK 441-103 is installed. This directive aims to mitigate the risk of structural failures that have been previously reported in the horizontal stabiliser attach bulkhead.

Key Provisions

The Civil Aviation Regulations 1998, Part 39, specifically under the Airworthiness Directives for the Cessna 400 Series Aeroplanes, include a directive (AD/CESSNA 400/98) that pertains to the horizontal stabiliser forward attach bulkhead. This directive applies to Model 441 serial numbers 441-001 through 441-0362 with time in service exceeding 3000 hours. The key requirements outlined in this directive (section 1) are for operators to inspect the horizontal stabiliser forward attach bulkhead for cracks and fretting, in accordance with Cessna Service Bulletin CQB91-1 Revision 1. If Service Kit SK 441-103 has been installed, operators must also inspect and adjust the gap between the F.S.404.145 bulkhead and the horizontal stabiliser aft attach points, following the Accomplishment Instructions of SK 441-103A. Operators of these aircraft must adhere to specific compliance timelines as stipulated by the regulations. For the initial inspection of the horizontal stabiliser forward attach bulkhead, it must be completed within 200 hours in service, at the next removal of the horizontal stabiliser, or before 30 April 1993, whichever occurs first. Subsequent inspections must occur at intervals not exceeding 2000 hours until Service Kit SK 441-103 is installed. For the inspection and adjustment of the gap when Service Kit SK 441-103 has been installed, this must be done within 200 hours in service, the next time there is access to the affected parts, or before 30 April 1993, whichever is earliest. Failure to comply with these requirements could result in significant legal consequences. While the specific penalties are not detailed in the directive, non-compliance with airworthiness directives under the Civil Aviation Regulations 1998 can lead to enforcement actions by the Civil Aviation Safety Authority (CASA). This may include the issuance of a Notice of Proposed Civil Penalty, which could result in substantial fines and other penalties. Additionally, continued operation of an aircraft that does not meet the mandated safety standards could be considered unsafe, leading to potential grounding of the aircraft and further regulatory action. The severity of the consequences depends on the extent of non-compliance and the risk posed to aviation safety.