COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Allison Turbine Engines - 250 Series
AD/AL 250/38 Idler Gearshafts - Replacement 10/79
Applicability: All 250-C28 and -C30 series models fitted with generator idler gearshaft P/N 6898980 or 6898591 and 77 tooth idler gearshaft P/N 6898652.
Document: | 1. | Allison 250-C28 CEB No. 72-2003; or Allison 250-C30 CEB No. 72-3003; or |
| 2. | FAA AD 79-16-06 Amendment 39-3527 also refers. |
Compliance: | 1. | For 250-C28 engines: Prior to reaching 9000 cycles. |
| 2. | For 250-C30 engines: Prior to reaching 2000 cycles. |
| 3. | For engines which may have exceeded the maximum permissible number of cycle at the time of promulgation of this Directive 3 September 1979, within 50 cycles. |
Background: This Directive is issued to prevent sudden power loss due to accessory drive gearbox gearshaft failure.
Overview
The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority, form the legislative framework governing aviation safety in Australia. Part 39, which includes the Airworthiness Directives, addresses specific maintenance and safety requirements for aircraft and their components. One such directive, AD/AL 250/38, pertains to Allison Turbine Engines, specifically the 250 Series, and mandates the replacement of idler gearshafts to prevent sudden power loss due to gearshaft failure. This directive was enacted to enhance aviation safety by mitigating the risk of in-flight mechanical failure, thereby protecting the lives of passengers and crew. The objective is to ensure that these critical components are maintained within specified cycle limits, which, if exceeded, could compromise engine performance and safety.
This legislative instrument, F2006B02252, was introduced by the Commonwealth of Australia to fill a critical gap in ensuring the ongoing airworthiness of specific turbine engine models. The directive applies to all 250-C28 and -C30 series models equipped with particular idler gearshafts, demanding that these parts be replaced before reaching certain operational cycle thresholds. By enforcing these maintenance requirements, the legislation aims to prevent catastrophic engine failures and maintain the high safety standards essential for civil aviation.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 106, which pertains to the Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to all Allison 250-C28 and -C30 series turbine engines that are fitted with the specified generator idler gearshafts. The legislation mandates the replacement of certain idler gearshafts to prevent sudden power loss due to gearshaft failure, thereby ensuring the continued airworthiness of these aircraft engines. This directive applies on a Commonwealth level across Australia, imposing compliance requirements on aircraft operators, maintenance providers, and other relevant entities within the aviation industry. The directive specifies different compliance timelines based on the engine model and cycle count, with the aim of ensuring timely and effective replacement of the idler gearshafts to maintain safety standards. The regulation does not explicitly mention any exclusions or exemptions, suggesting that it applies broadly to all entities and aircraft within its scope. The enforcement and detailed application of these directives may be further clarified or expanded through subordinate instruments or guidance documents issued by the Civil Aviation Safety Authority.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 106, outlines the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, including AD/AL 250/38, which mandates the replacement of idler gearshafts in Allison Turbine Engines - 250 Series. This directive applies to all 250-C28 and -C30 series models equipped with specific generator idler gearshaft parts numbers: 6898980 or 6898591, and 77 tooth idler gearshaft part number 6898652 (section 1). Compliance with this directive is imperative to ensure the safety of aviation operations by preventing sudden power loss due to accessory drive gearbox gearshaft failure.
Entities governed by this directive must adhere to the specified cycle limits for engine replacement. For 250-C28 engines, the replacement must occur before the engine reaches 9000 cycles. For 250-C30 engines, the replacement must occur before the engine reaches 2000 cycles (section 1). In cases where engines may have exceeded these limits at the time of the directive's issuance on 3 September 1979, the replacement must occur within 50 cycles from the directive's promulgation (section 1). Failure to comply with these requirements could result in significant safety hazards, compromising the integrity of the aircraft's operation.
The directive imposes clear obligations on engine operators and maintenance personnel. They are required to verify the engine's cycle count and ensure that the idler gearshafts are replaced as per the specified cycle limits. Additionally, documentation must be updated to reflect the replacement, including references to Allison 250-C28 CEB No. 72-2003, Allison 250-C30 CEB No. 72-3003, or FAA AD 79-16-06 Amendment 39-3527 (section 1). This ensures that all relevant parties are aware of the necessary actions and maintain accurate records of compliance.
Failure to comply with the provisions of this airworthiness directive may result in severe consequences. Civil aviation regulations do not specify particular offences or penalties for non-compliance with this directive, but non-compliance can lead to severe civil or criminal penalties under broader aviation safety laws. These may include fines, suspension of operational permits, or other enforcement actions deemed necessary by CASA to ensure compliance and maintain aviation safety standards. The seriousness of these penalties underscores the importance of adhering to the directive's requirements.