AD/BEECH 33/40 - Elevator Trim Tab Actuator

Overview

The Civil Aviation Regulations 1998, specifically within Part 39, addresses the critical issue of ensuring the airworthiness of aircraft by mandating specific maintenance directives. One such directive, AD/BEECH 33/40, targets the elevator trim tab actuators of Beechcraft 33 and 35-33 series aeroplanes, commonly known as Debonair/Bonanza. This directive was introduced following two fatal accidents where the elevator trim tab actuators were incorrectly interchanged during maintenance, leading to loss of control of the aircraft. The objective of this directive is to prevent such interchange by requiring maintenance actions in accordance with Beechcraft Service Bulletin 2399, and to ensure compliance at the next scheduled inspection following 29 February 1992. The policy objective is to enhance aviation safety by mandating specific actions to prevent critical maintenance errors that could compromise aircraft control.

Scope and Application

The Civil Aviation Safety Authority Schedule of Airworthiness Directives, specifically AD/BEECH 33/40, applies to Beechcraft 33 and 35-33 (Debonair/Bonanza) series aeroplanes with the models and serial numbers as outlined in Beechcraft Service Bulletin 2399. This regulation is applicable to aircraft maintenance and operational procedures, ensuring compliance with the specified action to prevent a known safety risk associated with the elevator trim tab actuators. The directive mandates adherence to the actions set out in Beechcraft Service Bulletin 2399, requiring corrective measures to be implemented at the next scheduled inspection following the effective date of the directive. This safety measure aims to address the critical issue of potential loss of control due to the reversal of the right-hand and left-hand trim tab actuators, which has been implicated in previous fatal accidents. The regulation extends its reach within the Commonwealth of Australia, overseen by the Civil Aviation Safety Authority, and is a critical component in maintaining the airworthiness of the specified aircraft models.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, under the authority of the Civil Aviation Safety Authority (CASA), outlines a Schedule of Airworthiness Directives for various aircraft. The directive AD/BEECH 33/40 pertains to the Beechcraft 33 and 35-33 (Debonair/Bonanza) series aeroplanes, addressing the elevator trim tab actuator issue (Section 2/92). The directive mandates compliance with Beechcraft Service Bulletin 2399, which is referenced in FAA AD 91-17-01 Amendment 39-7099. The directive applies to models and serial numbers listed in the specified Beechcraft Service Bulletin, and compliance must be achieved at the next scheduled inspection for Maintenance Release after 29 February 1992. The primary obligation under this directive is for aircraft operators to ensure that the elevator trim tab actuators are not interchanged. This requirement is crucial to prevent the risk of reversed actuators, which could lead to loss of control of the aircraft. The directive mandates actions as outlined in the referenced Beechcraft Service Bulletin 2399, which likely includes specific maintenance or inspection procedures to correctly install and verify the orientation of the trim tab actuators. Operators must adhere to these procedures to maintain the airworthiness of their aircraft. Failure to comply with the directive may result in severe consequences. Non-compliance could potentially lead to a recurrence of the accidents that prompted the directive, putting the safety of passengers and crew at risk. The regulations do not explicitly detail specific penalties within the provided text, but non-compliance with CASA directives generally can lead to enforcement actions by CASA, which may include fines, suspension or revocation of air operator certificates, and other regulatory sanctions. The potential for loss of control of an aircraft also implies a risk of criminal liability for those responsible, given the serious nature of the safety issue at hand.