AD/GAF-N22/34 - Horizontal Stabiliser Gust Lock - Installation

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105, address the safety and airworthiness of aircraft, with the Civil Aviation Safety Authority (CASA) administering these regulations. One such regulation is AD/GAF-N22/34, which mandates the installation of a horizontal stabiliser gust lock for GAF N22 and N24 series aeroplanes. This Airworthiness Directive was enacted to mitigate the risk of damage to the horizontal stabiliser and control system due to strong wind gusts, even when the pilot's control lock is engaged. The problem this directive aims to resolve is the vulnerability of certain aircraft models to wind-induced damage, thereby enhancing overall aviation safety. The policy objective is to ensure that these aircraft are maintained in a safe and airworthy condition by mandating specific modifications to prevent structural damage during adverse weather conditions.

Scope and Application

The Civil Aviation Safety Authority (CASA) has issued the Airworthiness Directive AD/GAF-N22/34 under the Civil Aviation Regulations 1998, which mandates the installation of a horizontal stabiliser gust lock for specific models of GAF N22 and N24 series aeroplanes. This directive applies to all N22, N22B, N24, and N24A models with serial numbers referenced in GAF Service Bulletin (SB) No. NMD-55-9. The directive aims to address instances where the horizontal stabiliser and control system have been damaged due to strong wind gusts, even when the pilot’s control lock was engaged. Compliance with this directive is required for aircraft manufactured before 1 August 1980, ensuring that these models meet the specified airworthiness standards to mitigate the risk of damage from wind gusts. The regulation's scope is confined to the specified aircraft models and serial numbers, and compliance must be verified in accordance with the guidelines provided in the referenced service bulletin.

Key Provisions

The Civil Aviation Regulations 1998, under Part 39 - 105, specifically address the airworthiness directives for GAF N22 and N24 series aeroplanes. One such directive, AD/GAF-N22/34, pertains to the installation of a horizontal stabiliser gust lock, as outlined in GAF SB No. NMD-55-9 (Section 105). This directive applies to all models N22, N22B, N24, and N24A with serial numbers as referenced in the aforementioned document. The requirement for compliance with this directive was established before 1 August 1980 due to documented instances of damage to the horizontal stabiliser and control system caused by strong wind gusts, even when the pilot’s control lock was engaged. This regulation imposes specific obligations on the owners and operators of the specified aircraft models. They must ensure that the horizontal stabiliser gust lock is installed as per the guidelines provided in GAF SB No. NMD-55-9. This includes verifying that the aircraft in question falls within the serial number range specified and that the installation is carried out by authorised personnel. Additionally, operators are responsible for maintaining records of compliance and ensuring that the aircraft remains airworthy at all times. Failure to comply with these airworthiness directives can result in significant legal and operational consequences. Under the Civil Aviation Act 1988, non-compliance may be considered an offence, potentially leading to civil penalties. The maximum penalty for contravening these regulations can include fines and, in severe cases, prosecution. Additionally, the aircraft may be grounded until the required modifications are completed, which can disrupt scheduled operations and lead to financial loss. The seriousness of these consequences underscores the importance of adhering to the airworthiness directives to ensure the safety and reliability of the aircraft.