AD/MU-2/34 - Engine Air Intake Bleed Air Tubing Coupling Nut Retorque, Inspection, Modification

Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of Australia, represent a critical framework for maintaining safety standards within the nation's aviation sector. Specifically, Part 39 - 105 of these regulations addresses the authority and procedures concerning airworthiness directives, which are mandatory safety measures that aircraft manufacturers and operators must comply with. The problem or gap these regulations were introduced to address includes ensuring the continued airworthiness of aircraft through timely and effective safety directives. This is achieved through the establishment of clear compliance requirements and the identification of specific aircraft models and serial numbers that must adhere to these directives. A particular example within this legislative instrument is the Airworthiness Directive AD/MU-2/34 concerning Mitsubishi MU-2 Series Aeroplanes. This directive was introduced to mitigate the risk of engine bleed air loss at the intake anti-ice coupling nut, which could lead to engine malfunction. The policy objective here is to enhance safety by mandating a retorque, inspection, and modification of the coupling nut, as outlined in Mitsubishi SB No. 196 Rev A. Compliance with this directive is mandatory for certain models and serial numbers of the MU-2 Series Aeroplanes, with an effective date set before any further flight after 31 July 1984.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 under the Civil Aviation Safety Authority's Schedule of Airworthiness Directives, pertains to Mitsubishi MU-2 series aeroplanes, covering models MU-2B/-10/-15/-20/-25/-26 with serial numbers ranging from 008 to 347, with the exceptions of serial numbers 313SA and 321SA, as well as models MU-2B-30/-35/-36 with serial numbers between 501 and 696, excluding serial numbers 652SA and 661SA. This legislative instrument mandates specific actions to be taken regarding the engine air intake bleed air tubing coupling nut to prevent potential malfunctions of the engine air intake anti-ice system, which could arise from the loss of bleed air at the intake anti-ice coupling nut. Compliance with these directives is required before any further flight after 31 July 1984, ensuring the safety and reliability of the aircraft in operation. This regulation extends across the Commonwealth of Australia, governed by the Civil Aviation Safety Authority, and applies to all relevant aircraft within the specified serial number ranges.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, include Airworthiness Directives (AD) that govern the operational safety of various aircraft types. Section AD/MU-2/34 pertains to Mitsubishi MU-2 Series Aeroplanes, addressing an issue related to the engine air intake bleed air tubing coupling nut. This directive mandates a retorque, inspection, and potential modification of the coupling nut to prevent the loss of engine bleed air, which could otherwise cause a malfunction in the engine air intake anti-ice system. Compliance with this directive is crucial and must be achieved before any further flight after 31 July 1984, as per the regulations. The obligations imposed by AD/MU-2/34 on the relevant parties include ensuring that the specified models of Mitsubishi MU-2 Series Aeroplanes undergo the required inspection and modification. Specifically, the directive applies to models MU-2B/-10/-15/-20/-25/-26 with serial numbers (S/Nos.) ranging from 008 to 347, with certain exceptions noted (S/Nos. 313SA and 321SA), and models MU-2B-30/-35/-36 with S/Nos. from 501 to 696, excluding S/Nos. 652SA and 661SA. The retorque, inspection, and any necessary modification of the bleed air tubing coupling nut must be carried out in accordance with Mitsubishi SB No. 196 Rev A, as referenced in the directive. Failure to comply with AD/MU-2/34 could result in serious safety risks, including potential engine malfunctions during flight. The directive is underpinned by JCAB AD No. TCD-2342-84, which highlights the importance of adhering to these safety measures. The penalties and consequences for non-compliance could include regulatory action against the aircraft operator or owner, potentially leading to grounding of the aircraft until the required inspections and modifications are completed. The specific penalties, however, are not detailed in the provided text but could range from fines to more severe aviation safety penalties under broader regulations.