AD/BEECH 18/8 - Undercarriage Limit Switch - Inspection

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105, includes a legislative instrument (F2006B03626) that was enacted to address the safety concerns associated with the operation of the undercarriage limit switch on Beechcraft 18 Series aeroplanes, particularly models C-18S and AT-11. This regulation was introduced to ensure the safety and reliability of aircraft operations by mandating a specific inspection and adjustment procedure for the undercarriage limit switch, which is crucial for the proper functioning of the aeroplane's landing gear system. The Civil Aviation Safety Authority, as the regulatory body under the Australian Government, established this directive to comply with the stringent safety standards outlined in the Australian National Aviation Orders (ANO). The policy objective is to mitigate potential risks associated with the landing gear system by ensuring the limit switch operates correctly within specified parameters. The legislative instrument mandates that the undercarriage limit switch be inspected and, if necessary, adjusted at regular intervals not exceeding 100 hours of service and after any work or adjustments to the switch or undercarriage, excluding routine oil and air additions. This proactive approach aims to prevent mechanical failures and enhance the overall safety of civil aviation operations in Australia.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 pertaining to the Civil Aviation Safety Authority's Schedule of Airworthiness Directives, applies to the Beechcraft 18 Series aeroplanes, specifically the models C-18S and AT-11. This regulation mandates that the non-retract limit switch on the port undercarriage leg of these aircraft must be inspected and, if necessary, adjusted to ensure it is operated by the oleo leg when it is at a specified distance from the fully extended position. The inspection must be performed at intervals not exceeding 100 hours of time in service and after any work or adjustments have been made to the switch or undercarriage, excluding routine oil and air additions. This regulation is applicable nationally within the Commonwealth of Australia and is enforced by the Civil Aviation Safety Authority. The regulation does not specify any exclusions or exemptions, but its requirements may be extended or modified through subordinate instruments as deemed necessary by the authority.

Key Provisions

The key operative sections of the Civil Aviation Regulations 1998, specifically AD/BEECH 18/8 concerning the Beechcraft 18 Series Aeroplanes, outline the requirements for inspecting and adjusting the non-retract limit switch on the port undercarriage leg. These provisions are critical for ensuring the safety and proper functioning of the aeroplane. According to section (1), the aeroplane must be raised slowly and evenly on jacks to inspect and, if necessary, adjust the limit switch. This adjustment must ensure that the switch is operated by the oleo leg when it is at a distance of no less than half an inch and no more than three-quarters of an inch from the fully extended position. Additionally, any sticking of the strut should be relieved by gently tapping the fork to ensure smooth extension. If adjustments have been made to relieve sticking during the inspection, the aeroplane should be re-raised to verify that the oleo leg operates the switch without requiring further action to relieve sticking. The obligations imposed by the regulations are detailed and specific. Operators and maintainers of Beechcraft 18 Series aeroplanes, particularly the C-18S and AT-11 models, must adhere to the outlined procedures for inspecting and adjusting the non-retract limit switch. This includes performing these inspections at intervals not exceeding 100 hours of service time and after any work or adjustments on the switch or undercarriage, excluding normal oil and air additions. Ensuring compliance with these requirements is crucial for maintaining the safety and airworthiness of the aircraft. The regulations also refer to ANO 105.1.4.3.6.8, which provides additional guidance and standards that must be followed. Breaches of these regulations can result in significant consequences. Under section (2), failure to comply with the specified inspection and adjustment procedures may lead to safety risks and potential regulatory penalties. Civil aviation authorities have the power to take action against operators and maintainers who do not adhere to the requirements, which can include fines and other penalties. The maximum penalties for non-compliance may vary, but they are designed to ensure that operators and maintainers take the necessary steps to keep their aircraft safe and airworthy. Ensuring adherence to these regulations is essential for preventing accidents and maintaining the integrity of the civil aviation system.