AD/DC3/32 - Elevator Control System - Inspection

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105, was enacted to address safety concerns and ensure compliance with airworthiness directives in the aviation industry. One such directive, AD/DC3/32, focuses on the inspection of the elevator control system for Douglas DC3 Series aeroplanes, including models DC-3, DC-3A, DC-3D, Super DC-3, and R4D. The directive was enacted by the Civil Aviation Safety Authority (CASA) to maintain and improve the safety standards of civil aviation in Australia. The primary objective of this directive is to ensure that the elevator control system is correctly rigged and that there is adequate clearance between the elevator cables, cable fittings, and the bulkhead frame and channel. This is crucial for preventing any interference that could compromise the safety of the aircraft during operation. Compliance with this directive is mandatory within 25 hours of time in service after 27 September 1978, unless the inspection has already been completed within the previous 100 hours of time in service.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, apply to all models of Douglas DC3 series aeroplanes, including the DC-3, DC-3A, DC-3D, Super DC-3, and R4D, ensuring that their elevator control systems are properly inspected and maintained. This regulation applies to aircraft registered in Australia and operated within Australian airspace, as well as to Australian operators of these aircraft worldwide. The regulation mandates that the elevator control system must be correctly rigged before conducting the required inspection, focusing on the right-hand and left-hand elevator upper cables and their fittings for potential interference with the bulkhead frame and channel located just aft of the control column assembly. Compliance with the directive involves checking the clearance of the elevator cables and fittings, particularly when the elevator horn of the control column is rotated to the lowest point of its movement arc, and making necessary adjustments if the clearance is insufficient. The regulation does not explicitly exclude any specific circumstances or provide for exemptions but applies universally to the specified aircraft models within the stated timeframe.

Key Provisions

The primary sections of the Civil Aviation Regulations 1998, specifically PART 39 - 105 Civil Aviation Safety Authority Schedule of Airworthiness Directives, detail mandatory inspections and compliance requirements for the Douglas DC3 series aeroplanes. Section AD/DC3/32 mandates an inspection of the elevator control system. This requirement is crucial for ensuring that the elevator control system operates correctly and safely before any flight operations. The regulation specifies that the inspection must focus on the right-hand (RH) and left-hand (LH) elevator upper cables and their fittings, ensuring they do not interfere with the bulkhead frame and channel located just aft of the control column assembly at specific fuselage stations for different models. Additionally, the cables and fittings must maintain a minimum clearance of 3/32" relative to the bottom of the cutout hole and both legs of the channel throughout the full travel of the cables. The obligations under this directive are clear and specific. Operators of Douglas DC3 series aeroplanes must ensure that the elevator control system is correctly rigged before conducting the inspection. This inspection is detailed, requiring operators to visually check for potential interference between the elevator cables and the bulkhead frame and channel. If the clearance is less than the required 3/32", operators must trim the cable cutout hole in the bulkhead frame and both legs of the channel to achieve a nominal clearance of 1/8" + 1/32" using a minimum 1/4" radius. All edges must be broken and smoothed to ensure safety and compliance. This inspection must be completed within 25 hours of time in service after 27 September 1978, or if it has already been completed within the previous 100 hours of time in service. Failure to comply with these provisions can result in significant legal consequences. While the specific penalties are not detailed within the text, non-compliance with Civil Aviation Safety Authority directives can lead to enforcement actions, fines, and potential grounding of the aircraft until the required inspections and necessary adjustments are made. The severity of these consequences underscores the importance of adhering to the regulations to ensure the safety and airworthiness of the aircraft.