COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
British Aerospace BAe 3100 (Jetstream) Series Aeroplanes
AD/JETSTREAM/14
Amdt 4
Flap Torque Tube Universal Joints 13/94
Applicability: All HP137 Mk1, Jetstream Series 200, 3100 and 3200 aircraft, except those which have the improved flap torque shaft assemblies introduced by Jetstream Service Bulletin 27-JA920340.
Note: The improved flap torque shaft assemblies were factory fitted beginning with constructor’s number 957.
Requirement: In accordance with British Aerospace Jetstream Alert Service Bulletin 27-A-JA 900544 Revision 3, or 4:
- Identify whether Type F or Type M universal joints are fitted to the LH and to the RH flap torque shaft assemblies.
2. Inspect Type F universal joints for cracks, visually, and using eddy currents.
3. Replace Type F universal joints with Type M universal joints.
Compliance: 1. Identify joint type before 15000 landings, or before exceeding 100 landings after 30 June 1990, whichever occurs later.
2. If a type F joint has been in service more than 15000 landings when identified, inspect before further flight after identification, and thereafter at intervals not exceeding 400 landings.
3. Replace not later than 15000 landings, or before exceeding 400 landings after 30 June 1990, whichever occurs later.
The provisions of the previous amendments are unchanged, this Amendment is effective from 8 December 1994.
Background: Two types of universal joints were fitted to the flap torque shaft assemblies. One, known as Type F, has a much shorter fatigue life than the other, known as Type M. This Directive first requires an inspection to determine which type is fitted to the aircraft. No further action is required for Type M joints, but Type F joints must be replaced before 15000 landings. For Type F joints that have already exceeded 15000 landings, safety is maintained by inspection for a short period to allow scheduling for the replacement.
Amendment 4 exempts aircraft which have the later, improved flap torque shaft assemblies. The wording of this Directive has also been revised, without changing the intent.
Overview
The Civil Aviation Regulations 1998, as amended, address critical safety concerns in the aviation sector, particularly regarding aircraft maintenance and airworthiness. Enacted by the Parliament of Australia, this legislation forms part of the regulatory framework overseen by the Civil Aviation Safety Authority (CASA) and aims to ensure the highest standards of safety and reliability in civil aviation. One specific area addressed by the regulations is the maintenance of British Aerospace BAe 3100 (Jetstream) Series Aeroplanes, where Amendment 4 to Airworthiness Directive AD/JETSTREAM/14 targets the replacement of certain flap torque tube universal joints to mitigate safety risks. This amendment was introduced to address the issue of differing fatigue lives between Type F and Type M universal joints, ensuring that older, less durable joints are replaced to prevent potential mechanical failures, thereby enhancing overall flight safety.
Scope and Application
The Civil Aviation Regulations 1998, particularly Part 39 - 105, governs the safety requirements for various aircraft within the Commonwealth of Australia. Specifically, this legislation applies to all HP137 Mk1, Jetstream Series 200, 3100, and 3200 aircraft, excluding those equipped with improved flap torque shaft assemblies introduced by Jetstream Service Bulletin 27-JA920340, which were factory fitted starting from constructor’s number 957. The regulation mandates that operators of the specified aircraft must identify whether Type F or Type M universal joints are fitted to the left-hand and right-hand flap torque shaft assemblies. For Type F universal joints, inspections are required for cracks using visual and eddy current methods, and these joints must be replaced with Type M universal joints. Compliance with these directives requires identification and inspection before 15,000 landings or within 100 landings post-30 June 1990, whichever is later, and replacement within 15,000 landings or 400 landings post-30 June 1990, whichever is later. This amendment became effective from 8 December 1994, ensuring safety standards are maintained through specific operational and maintenance protocols.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, include a Schedule of Airworthiness Directives that govern the maintenance and operation of British Aerospace BAe 3100 (Jetstream) Series Aeroplanes. One such directive, AD/JETSTREAM/14 Amendment 4, pertains to flap torque tube universal joints. This directive applies to all HP137 Mk1, Jetstream Series 200, 3100, and 3200 aircraft, excluding those with improved flap torque shaft assemblies introduced from constructor’s number 957 onwards. The directive mandates identifying whether Type F or Type M universal joints are installed on the left-hand (LH) and right-hand (RH) flap torque shaft assemblies, in accordance with British Aerospace Jetstream Alert Service Bulletin 27-A-JA 900544 Revision 3 or 4.
The directive outlines specific obligations and requirements for the aircraft operators and maintenance personnel. Operators must first identify the type of universal joints fitted to their aircraft. If Type F universal joints are identified, they must be inspected for cracks visually and using eddy currents. Following this inspection, Type F universal joints must be replaced with Type M universal joints. The directive provides a timeline for compliance: identification must occur before 15,000 landings or before exceeding 100 landings after 30 June 1990, whichever is later. Replacement of Type F joints must occur no later than 15,000 landings or before exceeding 400 landings after 30 June 1990. For Type F joints already in service beyond 15,000 landings at the time of identification, inspections must be conducted before further flight and at intervals not exceeding 400 landings.
Failure to comply with this directive may result in serious safety concerns, potentially leading to operational risks and legal consequences. The Civil Aviation Regulations do not specify explicit penalties for non-compliance within this directive. However, non-compliance could result in the aircraft being deemed unairworthy, leading to potential enforcement actions by the Civil Aviation Safety Authority (CASA). Such actions may include fines, suspension or revocation of airworthiness certificates, and other regulatory measures to ensure compliance and maintain aviation safety standards.