AD/P68/21 - Horizontal Stabilator to Fuselage Frame Attachment - Check Torque

Overview

The Civil Aviation Regulations 1998 were enacted by the Parliament of Australia to regulate civil aviation safety across the country. The legislation aims to ensure that all civil aviation activities and aircraft in Australia comply with international safety standards. A specific piece of legislation under this act is the Airworthiness Directive (AD) for Partenavia P68 Series Aeroplanes, issued in 1983. This directive was introduced to address a critical safety issue related to the horizontal stabilator to fuselage frame attachment in certain Partenavia P68 aircraft. The policy objective behind AD/P68/21 is to ensure that the torque of specific bolts is within the correct range to maintain the integrity and safety of the aircraft during flight. This directive applies to a specific range of serial numbers for Partenavia P68 aircraft, excluding certain models, and requires that the bolts securing the horizontal stabilator torque tube brackets to the fuselage frame be checked and, if necessary, retorqued to the specified value of 78-83 LB inches before further flight.

Scope and Application

The Civil Aviation Safety Authority Schedule of Airworthiness Directives, specifically AD/P68/21, applies to all Partenavia P68, P68B, P68C, P68C-TC, and P68 Observer aeroplanes with serial numbers ranging from 1 to 289, excluding S/Nos. 234, 256, 259, 269, and 288. This directive pertains to the attachment of the horizontal stabilator to the fuselage frame, focusing on the torque of AN4-6A bolts that secure the horizontal stabilator torque tube brackets to the fuselage frame. The requirement necessitates a check of the torque on these bolts, with a mandate to retorque them to the correct value of 78-83 LB inches if necessary. This directive is applicable within the national jurisdiction of Australia and is enforced by the Civil Aviation Safety Authority. The directive does not explicitly mention any exclusions, exemptions, or thresholds but is complemented by subordinate instruments such as RAI AD 83-3 and Partenavia Service Bulletin No. 57 to ensure comprehensive compliance. Compliance must be achieved before further flight, underscoring the critical nature of the directive for maintaining airworthiness standards.

Key Provisions

The Civil Aviation Regulations 1998, specifically in Part 39 - 105, under the Civil Aviation Safety Authority Schedule of Airworthiness Directives, contains provisions for the Partenavia P68 series aeroplanes. In this case, the relevant directive is AD/P68/21, which mandates a check on the torque of the AN4-6A bolts securing the horizontal stabilator torque tube brackets to the fuselage frame (section 1). The requirement is that these bolts must be checked and, if necessary, retorqued to the correct value of 78-83 LB inches (section 2). This directive applies to all Partenavia P68, P68B, P68C, P68C-TC, and P68 Observer aircraft with serial numbers (S/Nos.) ranging from 1 to 289, except for S/Nos. 234, 256, 259, 269, and 288 (section 3). Compliance with AD/P68/21 is mandatory before any further flight of the specified aircraft. The directive ensures that the horizontal stabilator is securely attached to the fuselage frame, which is critical for maintaining the aircraft's stability and control during flight. This requirement underscores the importance of regular and thorough maintenance checks to prevent potential failures that could compromise flight safety (section 4). The regulations impose specific obligations on the parties or entities governed by this directive. Aircraft owners, operators, and maintenance personnel must adhere to the directive by ensuring that the torque of the specified bolts is checked and adjusted if necessary, prior to any subsequent flight. This involves conducting a detailed inspection and potentially making adjustments to the bolts to meet the required torque value of 78-83 LB inches. The directive references RAI AD 83-3 and Partenavia SB No. 57, which provide further technical details and guidance on the compliance process (section 5). Failure to comply with the provisions of AD/P68/21 may result in significant consequences. The Civil Aviation Regulations 1998 do not explicitly state penalties for non-compliance in this particular directive. However, non-compliance with airworthiness directives generally can lead to enforcement actions by the Civil Aviation Safety Authority, which may include grounding of the aircraft, fines, or other regulatory penalties. Ensuring adherence to these directives is crucial to maintaining the safety and airworthiness of the aircraft, thereby protecting the lives of passengers and crew (section 6).