AD/BELL 206/115 - Horizontal Stabilizer P/N 206-023-119-151

Overview

The Civil Aviation Safety Authority (CASA) introduced F2006B04429 in 2006 to address safety concerns identified in the Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 series helicopters, specifically relating to the horizontal stabilizer. This legislative instrument is a regulation under the Civil Aviation Regulations 1998, established to ensure that airworthy standards are maintained and to mitigate risks associated with the identified defect. The Federal Government enacted this regulation to mandate safety checks and requirements on the specified helicopter models, ensuring compliance with international safety standards following a determination by the Federal Aviation Administration (FAA) that the horizontal stabilizers in question were either incorrectly manufactured or repaired, which could compromise the structural integrity and safety of the aircraft. The policy objective of this regulation is to mandate the inspection and replacement of the horizontal stabilizers on certain Bell Helicopter models to prevent potential catastrophic failures, thereby enhancing aviation safety and protecting both crew and passengers. This directive was implemented in response to a significant safety concern where a stabilizer had separated from the aircraft, striking the tail rotor and resulting in potential damage and risk of further accidents.

Scope and Application

The Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives applies to the specified Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series helicopters, specifically models 206L, 206L-1, and 206L-3. This regulation is a part of the overarching Civil Aviation Regulations 1998, which govern the airworthiness of aircraft in Australia, thereby ensuring safety and consistency in aviation practices. The directive mandates that operators inspect the horizontal stabilizer to ascertain if the raised external doubler is installed, a critical safety measure for the integrity of the stabilizer surface. Operators must remove any helicopter from service that lacks this doubler, which is identifiable by its position extending approximately 100 mm (4 inches) outward from either side of the tail boom and covering the upper surface of the stabilizer from within 12 mm (1/2 inch) of the forward leading edge to the trailing edge. While the directive is clear about the removal of non-compliant stabilizers, it also notes that the installation of an external doubler does not ensure conformity or an equivalent level of safety, indicating a need for adherence to the approved type design. The directive is in response to findings by the Federal Aviation Administration (FAA) regarding potential manufacturing or repair defects that may compromise the structural integrity of the stabilizers, with documented cases of stabilizer separation leading to severe consequences. Compliance with this directive is mandatory for continued flight operations post 20 October 1989, underscoring the urgency and importance of adhering to these safety standards.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, includes an Airworthiness Directive (AD) for Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 series helicopters. This directive, designated AD/BELL 206/115, concerns the horizontal stabilizer part number 206-023-119-151 13/89TX, and applies to models 206L, 206L-1 and 206L-3. The directive mandates an inspection of the horizontal stabilizer to ascertain whether the raised external doubler is installed (section 1). The doubler should be visible on the top surface of the stabilizer, extending approximately 100 mm (4 inches) outward from either side of the tail boom, and should cover the upper surface of the horizontal stabilizer from within 12 mm (1/2 inch) of the forward leading edge to the trailing edge. If the doubler is not installed, the stabilizer must be removed from service (section 1). It is important to note that installing an external doubler will not bring the stabilizer into conformity or provide an equivalent level of safety (Note 1). This AD references FAA AD 89-20-13 (Note 2). Compliance with this directive is required prior to any further flight after 20 October 1989. The obligations imposed by this directive are clear and specific. Operators and owners of the affected Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 series helicopters must ensure that the horizontal stabilizer is inspected as per the directive. This involves visually confirming the presence of the raised external doubler on the stabilizer. If the doubler is not present, the helicopter cannot be flown until the stabilizer is removed from service. This inspection and any necessary actions must be completed before any further flight after the specified date of 20 October 1989. Failure to comply with the requirements of AD/BELL 206/115 can result in serious consequences. The Federal Aviation Administration (FAA) has determined that the horizontal stabilizers in question may not meet the required specifications due to manufacturing or repair errors, potentially leading to catastrophic failure. If the horizontal stabilizer separates from the aircraft, as has occurred previously, it could strike the tail rotor, leading to significant safety risks. While the Civil Aviation Regulations 1998 do not specify penalties for non-compliance with this directive, operating an aircraft that does not meet airworthiness standards can result in severe consequences, including criminal charges, fines, and potential grounding of the aircraft.