AD/GAF-N22/26 - Rudder Tab Mass Balance Hinge Pin - Inspection

Overview

The Civil Aviation Regulations 1998, amended through legislative instrument F2006B10173, were enacted by the Commonwealth of Australia to regulate civil aviation safety, particularly focusing on airworthiness directives for specific aircraft models. This particular amendment targets the GAF N22 and N24 series aeroplanes, addressing a critical issue identified with the rudder tab mass balance hinge pin on certain models. The problem it addresses is the risk of the hinge pin seizing in its bush and shearing the split pin, which could potentially lead to a loss of control over the aircraft. The policy objective is to ensure the continued airworthiness of these aircraft by mandating regular inspections and compliance with specific service bulletins, as outlined in GAF Alert SB No. ANMD-55-6. This directive applies to all N22, N22B, N24, and N24A models with modification N39 that were fitted and delivered before 1 March 1979. The compliance requirement stipulates that inspections must be conducted within 50 hours of time in service after 16 March 1979, and then at intervals not exceeding 100 hours of time in service, until the modifications specified in the aforementioned service bulletin are implemented. The regulation is overseen by the Civil Aviation Safety Authority to ensure adherence to safety standards and to mitigate risks associated with the identified issue.

Scope and Application

The Civil Aviation Safety Authority Schedule of Airworthiness Directives, specifically AD/GAF-N22/26, pertains to the GAF N22 and N24 series aeroplanes, addressing the inspection of the rudder tab mass balance hinge pin. This directive applies to all models N22, N22B, N24, and N24A with Mod. N39 that were fitted and delivered before 1 March 1979. The directive mandates compliance within 50 hours of time in service after 16 March 1979 and requires subsequent inspections at intervals not exceeding 100 hours of time in service until modifications are made as per GAF Alert SB No. ANMD-55-6. This directive is integral to ensuring the safety and airworthiness of the specified aircraft models, following an incident where the rudder tab mass balance hinge pin seized, leading to the shearing of the split pin retaining the hinge pin. The directive's application is national, extending throughout Australia under the purview of the Civil Aviation Regulations 1998.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, include a Schedule of Airworthiness Directives that governs the maintenance and operation of various aircraft, including the GAF N22 and N24 series aeroplanes. Under this regulation, AD/GAF-N22/26 mandates the inspection of the rudder tab mass balance hinge pin for certain models of these aircraft (Part 39 - 105, AD/GAF-N22/26). This directive applies to all N22, N22B, N24, and N24A models with Mod. N39 fitted and delivered before 1 March 1979 (Part 39 - 105, AD/GAF-N22/26, Applicability). Compliance with this directive requires the inspection to be performed within 50 hours of time in service after 16 March 1979 and subsequently at intervals not exceeding 100 hours of time in service until the modification is completed in accordance with Alert SB No. ANMD-55-6 (Part 39 - 105, AD/GAF-N22/26, Compliance). This directive is issued in response to an incident where the rudder tab mass balance hinge pin seized in its bush and subsequently sheared the split pin retaining the hinge pin (Part 39 - 105, AD/GAF-N22/26, Background). The obligations under this directive are clear and specific. Aircraft operators must ensure that the inspection of the rudder tab mass balance hinge pin is carried out meticulously within the stipulated timeframes. This involves a thorough examination of the hinge pin to identify any signs of seizing in its bush or damage to the split pin. Operators must document each inspection and any necessary modifications in accordance with the guidelines provided in Alert SB No. ANMD-55-6. Failure to adhere to these obligations can lead to serious safety concerns, as the integrity of the rudder tab mass balance is crucial for the safe operation of the aircraft. Breaching the provisions of the Civil Aviation Regulations 1998 can result in both civil and criminal consequences. Under this particular directive, non-compliance with the mandated inspections and modifications could lead to penalties. While the specific penalties are not detailed in the legislative text provided, it is known that violations of civil aviation regulations can result in fines, enforcement actions, and potential grounding of the aircraft until compliance is achieved. In severe cases, criminal charges may also be pursued, leading to more substantial penalties and potential imprisonment for individuals responsible for the oversight. It is imperative for all stakeholders, including aircraft operators, maintenance personnel, and regulatory bodies, to be fully aware of and comply with these directives to ensure the highest standards of aviation safety are maintained. The directive's focus on the rudder tab mass balance hinge pin highlights the importance of regular and meticulous inspections to prevent potential failures that could compromise the safety of the aircraft and its occupants.