COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Bell Helicopter Textron Canada (BHTC) 222 Series Helicopters
AD/BELL 222/5 Ng Operating Speed Restrictions 11/85
Applicability: Bell 222U helicopters with Lycoming LTS101-750C-1 engines installed which have not been modified in accordance with LYC SB 101C-72-00-0079.
Requirement: Install engine operating speed restriction placard/ decal P/N 222-075-221-101 or similar, which reads:
AVOID CONT OPS 86% to 90% Ng
beneath gas producer speed indicators in accordance with Bell Helicopter Textron Alert Service Bulletin No. 222U-85-6.
Note: Temporary Revision No. 85-1 to Model 222U Flight Manual BHT-222U-FM-1 is required whilst this restriction is effective.
Effective: Forthwith.
Background: A number of contained turbine blade failures have occurred due to fatigue caused by vibration stresses when engines are operated in the 86% to 90% speed range. This Directive is issued restricting operation in this range until gas producer turbine wheels are modified in accordance with LYC SB 101C-72-00-0079.
Overview
The Civil Aviation Regulations 1998, enacted by the Commonwealth of Australia, were established to regulate civil aviation safety and address gaps in the regulatory framework to ensure the safety of aircraft operations. The legislation aims to mitigate risks and ensure the highest safety standards in civil aviation. PART 39 - 105 of the Civil Aviation Regulations 1998, which includes the Civil Aviation Safety Authority Schedule of Airworthiness Directives, specifically targets safety directives for particular aircraft models. For instance, AD/BELL 222/5 mandates operating speed restrictions for Bell Helicopter Textron Canada (BHTC) 222 Series Helicopters to prevent turbine blade failures due to fatigue caused by vibration stresses when engines are operated in a specific speed range. This directive requires the installation of an engine operating speed restriction placard or decal, effectively addressing the problem of contained turbine blade failures. The policy objective is to ensure the safety of aircraft operations by imposing necessary restrictions and modifications until the root cause of the failures is resolved.
Scope and Application
The Civil Aviation Regulations 1998, under PART 39 - 105, specifies that the Airworthiness Directives apply to Bell Helicopter Textron Canada (BHTC) 222 Series Helicopters, more specifically to Bell 222U helicopters equipped with Lycoming LTS101-750C-1 engines that have not been modified in accordance with LYC SB 101C-72-00-0079. The directive mandates the installation of a specific engine operating speed restriction placard or decal to mitigate the risk of contained turbine blade failures due to fatigue and vibration stresses observed in the 86% to 90% Ng speed range. This requirement must be fulfilled in line with Bell Helicopter Textron Alert Service Bulletin No. 222U-85-6, and a temporary revision to the Model 222U Flight Manual BHT-222U-FM-1 is also necessary during the implementation of this restriction. The directive is effective immediately, reflecting the urgency to address the identified safety concerns. The regulations are enforceable across the Commonwealth of Australia, ensuring consistent safety standards are maintained throughout the nation.
Key Provisions
The Civil Aviation Regulations 1998, specifically in Part 39 under the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, address the safety of Bell Helicopter Textron Canada (BHTC) 222 Series Helicopters. A key provision in this regard is AD/BELL 222/5, which pertains to operating speed restrictions for Bell 222U helicopters equipped with Lycoming LTS101-750C-1 engines that have not undergone a specific modification (section 11/85). The requirement here is the installation of an engine operating speed restriction placard/decal, specifically P/N 222-075-221-101 or a similar one, clearly indicating the restriction to avoid continuous operations between 86% to 90% Ng (section 11/85). This placard must be placed beneath the gas producer speed indicators in accordance with Bell Helicopter Textron Alert Service Bulletin No. 222U-85-6.
The obligations imposed by this directive are stringent and must be adhered to by the operators of Bell 222U helicopters. Operators must ensure that the specified engine operating speed restriction placard/decal is installed correctly and visibly beneath the gas producer speed indicators. Additionally, operators must refer to the Temporary Revision No. 85-1 to Model 222U Flight Manual BHT-222U-FM-1 during the period when this restriction is in effect (section 11/85). These measures are crucial to mitigate the risk of turbine blade failures due to fatigue from vibration stresses at the specified engine speeds.
Failure to comply with the provisions outlined in AD/BELL 222/5 can result in severe consequences. While the specific civil or criminal penalties for non-compliance are not detailed in the directive, it is clear that such non-compliance can lead to significant safety risks and potential regulatory action. The directive is effective forthwith, underscoring the urgency and importance of adhering to these safety measures. Operators who neglect these requirements risk not only the safety of their operations but also potential legal repercussions from CASA.