COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Eurocopter AS 350 (Ecureuil) Series Helicopters
AD/ECUREUIL/40 Tail Rotor Gearbox Casing 1/88
Applicability: All model AS 350 series helicopters.
Requirement: 1. Inspect the tail rotor gearbox casing in accordance with Para 1C(2) of SB No.
05.18.
2. Inspect and modify the tail rotor gearbox in accordance with Para 1C(3) of SB No. 05.18.
Compliance: For Para 1. Within 50 hours time in service after 25 November 1987 and thereafter at intervals not exceeding 50 hours time in service, until modification AMS 350A07- 8535 (polishing blend radii) is incorporated. After modification, inspect at intervals not exceeding 400 hours time in service.
For Para 2. Prior to exceeding 1100 hours total time in service or within 100 hours time in service after 25 November 1987, whichever is the later.
Background: The manufacturer has received reports at cracking in the blade horn support yoke radius just inboard at where the tail rotor control bellcrank pivot bolt is located.
Overview
The Civil Aviation Regulations 1998, enacted by the Commonwealth of Australia, serve to regulate the safety and operational standards in civil aviation. The regulations, particularly Part 39, establish specific airworthiness directives to address identified safety concerns and ensure the continued safety and reliability of aircraft. One such directive, AD/ECUREUIL/40, specifically targets the tail rotor gearbox casing of Eurocopter AS 350 (Ecureuil) series helicopters. This directive was introduced to address the problem of cracking in the blade horn support yoke radius, which is a critical safety concern identified by the manufacturer. The directive requires regular inspections and modifications of the tail rotor gearbox casing to mitigate the risk of failure due to this identified issue, thereby ensuring the continued airworthiness of the affected aircraft. The objective is to maintain high safety standards in civil aviation by addressing specific mechanical issues that could compromise the safety of flight operations.
Scope and Application
The Civil Aviation Regulations 1998, specifically under PART 39 - 105, pertains to the regulation of airworthiness directives, and includes detailed instructions concerning Eurocopter AS 350 (Ecureuil) series helicopters, with a focus on the tail rotor gearbox casing. This legislation applies to all model AS 350 series helicopters and is enforced by the Civil Aviation Safety Authority. The regulations mandate inspections and modifications of the tail rotor gearbox casing to address reported cracking issues in the blade horn support yoke radius, particularly at the location where the tail rotor control bellcrank pivot bolt is situated. Compliance with these directives is crucial and requires inspections to be conducted within 50 hours time in service after a specified date, and subsequently at intervals not exceeding 50 hours until certain modifications are implemented, after which inspections must occur at intervals not exceeding 400 hours. Additionally, specific modifications must be performed prior to the helicopter exceeding 1100 hours of total time in service or within 100 hours of a particular date, whichever is later. This legislation is binding on all entities operating AS 350 series helicopters within the Commonwealth of Australia, with no stated exclusions or exemptions, and its application extends through subordinate instruments as specified.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105 under the Civil Aviation Safety Authority Schedule of Airworthiness Directives, contains an airworthiness directive for Eurocopter AS 350 (Ecureuil) Series Helicopters. This directive, AD/ECUREUIL/40, pertains to the tail rotor gearbox casing and outlines the necessary inspections and modifications to ensure safety. The directive applies to all model AS 350 series helicopters and provides detailed instructions on how to conduct these inspections and modifications. According to section 1, the tail rotor gearbox casing must be inspected in accordance with Paragraph 1C(2) of Service Bulletin No. 05.18. Following this inspection, the tail rotor gearbox must then be inspected and modified in line with Paragraph 1C(3) of the same Service Bulletin.
The obligations imposed by this directive require operators of AS 350 series helicopters to conduct regular inspections of the tail rotor gearbox casing and make any necessary modifications. As per section 1, the initial inspection must occur within 50 hours of time in service after 25 November 1987 and should be repeated at intervals not exceeding 50 hours time in service until the modification AMS 350A07-8535 (polishing blend radii) is implemented. After this modification, inspections must take place at intervals not exceeding 400 hours time in service. Furthermore, for Paragraph 2, the inspection and modification must be completed prior to the helicopter exceeding 1100 hours total time in service, or within 100 hours time in service after 25 November 1987, whichever comes later.
Failure to comply with the provisions of this airworthiness directive can result in serious safety implications, as the directive addresses the potential for cracking in the blade horn support yoke radius just inboard of the tail rotor control bellcrank pivot bolt. While the specific penalties for non-compliance are not detailed within the text of the directive itself, non-compliance with airworthiness directives generally can result in significant civil or criminal consequences. This may include fines, imprisonment, or other legal actions as prescribed by the Civil Aviation Act 1988 and associated regulations. Operators are advised to adhere strictly to the outlined requirements to ensure the continued airworthiness of their aircraft and the safety of all personnel involved.