AD/TB10/6 Amdt 1 - Horizontal Stabilizer Balance Weight Support

Overview

The Civil Aviation Regulations 1998, which were enacted by the Australian Parliament, form a comprehensive regulatory framework governing all aspects of civil aviation within Australia. One specific legislative instrument under this Act is the AD/TB10/6 Amendment 1, pertaining to the Aerospatiale (Socata) TB9 and TB10 (Tobago) Series Aeroplanes. This amendment, introduced to address safety concerns associated with the horizontal stabilizer balance weight support, was published in 1985. The objective is to prevent the possibility of flutter by ensuring the separation of natural frequencies between the balance weight support and the stabilizer, as specified in the manufacturer’s directive SOCATA S.B. No. 25 ATA 55-10, and aligning it with the French AD 85-90-(A). Compliance with this directive is mandatory for all model TB9 and TB10 aircraft with serial numbers ranging from 001 to 474 inclusive, with the requirement to be met prior to 30 June 1986.

Scope and Application

The Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, specifically AD/TB10/6 Amendment 1, applies to all Aerospatiale (Socata) TB9 and TB10 (Tobago) series aeroplanes with serial numbers ranging from 001 to 474 inclusive. This directive mandates that modifications be made to the horizontal stabilizer balance weight support in accordance with SOCATA S.B. No. 25 ATA 55-10, which aligns with the requirements set out in the Bureau Veritas AD 85-90-(A). The directive aims to address a safety issue by separating the natural frequencies of the balance weight support and the stabilizer, thereby preventing the possibility of flutter. Compliance with this directive must be achieved prior to 30 June 1986, ensuring that all affected aircraft meet the specified safety standards set by the manufacturer and CASA. This regulation applies nationally within the Commonwealth of Australia and is enforced by CASA, which oversees civil aviation safety. The scope of the directive is limited to the specified serial numbers of the TB9 and TB10 models, and it does not explicitly mention any exclusions or exemptions. The application of the directive is further extended or refined through subordinate instruments that may provide additional details or specifications regarding the implementation of the required modifications.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, includes an Airworthiness Directive (AD) aimed at enhancing the safety of Aerospatiale (Socata) TB9 and TB10 (Tobago) series aeroplanes. The AD in question, AD/TB10/6 Amendment 1, pertains to the horizontal stabilizer balance weight support and applies to all model TB9 and TB10 aircraft with serial numbers ranging from 001 to 474 inclusive (section 1). The directive mandates that the action taken must comply with SOCATA Service Bulletin No. 25 ATA 55-10 (section 2). The requirement is rooted in a modification suggested by the manufacturer to separate the natural frequencies of the balance weight support and the stabilizer, thereby eliminating the risk of flutter. The compliance deadline for this directive was prior to 30 June 1986. The AD imposes specific obligations on the operators and owners of the affected aircraft. They must ensure that the modifications are carried out in strict accordance with the requirements outlined in SOCATA Service Bulletin No. 25 ATA 55-10 (section 2). This involves a detailed modification process that has been designed to prevent flutter, which could potentially compromise the aircraft's stability and safety. Operators and owners must ensure that all modifications are completed and that the aircraft is airworthy as per the specified requirements. Failure to comply with the AD/TB10/6 Amendment 1 can result in significant legal and safety consequences. Although the specific penalties are not detailed within this AD, non-compliance with airworthiness directives under the Civil Aviation Regulations 1998 can generally lead to serious repercussions. This can include fines, suspension of the aircraft's operating certificate, or even criminal charges in cases of severe non-compliance that lead to accidents or safety breaches. The Civil Aviation Safety Authority (CASA) enforces these regulations rigorously to maintain the highest safety standards in the aviation industry.