COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Fokker F100 (F28 Mk 100) Series Aeroplanes
AD/F100/12 Main Wheel Assembly 4/99
Applicability: F.28 Mk.0100 aircraft, all serial numbers equipped with ABS Corporation Main Wheel Assembly P/N 5008142-4, Serial numbers APR91-0570 through FEB93-0965.
Requirement: 1. Determine the Part number and Serial number of the Demountable Flange (inboard) Wheel Sub Assembly and the Demountable Flange (outboard) Wheel Sub Assembly.
For the purposes of this AD, no further action against the Demountable Flange (inboard) Wheel sub assembly is required unless the sub assembly has a Part Number 5008142-4 and a serial number within the following ranges:
APR91-0570 through OCT92-0858; or
S-APR91-0097 through S-MAY92-0126.
For the purposes of this AD, no further action against the Demountable Flange (outboard) Wheel sub assembly is required unless the sub assembly has a Part Number 5008140-1 and a serial number within the following ranges:
APR91-0570 through FEB93-0965; or
S-MAR91-0002 through S-FEB93-0100.
Note 1: Spares of both sub assemblies are affected by the requirements of this AD.
2. For the inboard Wheel Sub Assemblies, inspect in accordance with Section II - Accomplishment Instructions, Paragraph C of ABS Corporation (ABSC) Service Bulletin SB Fo100-32-46 dated Dec 24, 1992.
For the outboard Wheel Sub Assemblies , inspect in accordance with Section II - Accomplishment Instructions, Paragraph B of ABSC SB Fo100-32-48 dated Mar 10, 1993.
If damage or cracks are discovered during the inspection on either the inboard or outboard Wheel sub assemblies, then replace the damaged assembly before further flight. Inboard/outboard Wheel sub assemblies affected by this AD may be used as suitable replacements, provided Requirement 3 of this AD has been completed prior to fitment.
3. Repair the inboard Wheel Sub Assembly in accordance with Section II - Accomplishment Instructions, Paragraph D of ABSC SB Fo100-32-46 dated Dec 24, 1992.
Repair the outboard Wheel Sub Assembly in accordance with Section II - Accomplishment Instructions, Paragraph C of ABSC Fo100-32-48 dated Mar 10, 1993.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Note 2: The repair of the Outboard Wheel sub assembly in accordance with the above constitutes terminating action for this AD. However, the applicable Component Maintenance Manual contains continuing inspection requirements.
4. Inspect the Inboard Wheel Sub Assembly in accordance with Section II - Accomplishment Instructions, Paragraphs B.1 and C of ABSC SB Fo100-32-46 dated Dec 24, 1992.
Note 3: RLD BLA 93-009/3(A) refers.
Note 4: Fokker Service Bulletins F100-32-070 and F100-32-073 refer.
Compliance: 1. Within 3 months after the effective date of this AD.
2. For wheel assemblies with less than 800 flight cycles, inspect before 900 flight cycles, or within 200 flight cycles or at the next tyre chance, whichever occurs first.
For wheel assemblies with greater than 800 flight cycles, inspect within the next 100 flight cycles or at next tyre change, whichever occurs first.
In both cases, reinspect no later than every 500 flight cycles or at each tyre change, whichever occurs first. Continue to inspect until Requirement 3 of this AD becomes effective.
3. After the third inspection under Requirement 2 of this AD and before further flight after that inspection.
4. At the next two tyre changes after being repaired in accordance with Requirement 3 of this AD. Thereafter at every Wheel Assembly overhaul.
This Airworthiness Directive becomes effective on 22 April 1999.
Background: Several F.28 Mk.0100 operators reported finding cracks and broken spokes on Main Wheel Assemblies P/N 5008131-4. Investigation revealed that the manufacturer of the wheels, ABS Corporation, had discontinued a shot-peening procedure which was part of the manufacturing process before April 1991. As a result, a number of units were produced which are prone to fretting and cracking, due to the lack of shot- peening of the assembly mating surfaces and bolt bosses.
Overview
The Civil Aviation Regulations 1998, enacted by the Commonwealth of Australia, aims to ensure the safety of civil aviation operations through comprehensive regulations. Part 39 of these regulations specifically addresses airworthiness directives, including AD/F100/12 which pertains to Fokker F100 (F28 Mk 100) series aeroplanes. This Airworthiness Directive was introduced to address a safety issue identified with the main wheel assemblies of certain Fokker F100 aircraft, specifically those equipped with ABS Corporation Main Wheel Assembly parts. The directive was prompted by reports of cracks and broken spokes in the wheel assemblies, traced back to a manufacturing process change by the supplier that led to increased susceptibility to fretting and cracking. The directive outlines specific inspection and repair requirements for the affected wheel assemblies to ensure continued airworthiness and safety of the aircraft. Compliance with these directives is mandatory to maintain the safety standards set forth by the Civil Aviation Safety Authority.
Scope and Application
The Civil Aviation Regulations 1998, as detailed in Part 39 - 105 Civil Aviation Safety Authority Schedule of Airworthiness Directives, specifically targets the Fokker F100 (F28 Mk 100) Series Aeroplanes, particularly those equipped with ABS Corporation Main Wheel Assembly P/N 5008142-4, serial numbers ranging from APR91-0570 through FEB93-0965. This regulation applies to all aircraft operators, maintenance providers, and any other entities involved in the maintenance, inspection, or operation of the specified aircraft. The directive mandates particular actions concerning the main wheel assemblies, including determining part and serial numbers, conducting inspections for damage or cracks, and repairing or replacing affected components. Geographic reach is national, as these regulations are enforced across Australia under the Commonwealth's jurisdiction. The directive provides specific exclusions and thresholds for inspections and repairs, with detailed timelines and conditions for compliance based on the number of flight cycles. The scope of the directive may be extended or modified through subordinate instruments, such as service bulletins or maintenance manuals, which are referenced within the regulation.
Key Provisions
The Civil Aviation Regulations 1998, Part 39, under the Airworthiness Directives (AD) concerning Fokker F100 (F28 Mk 100) Series Aeroplanes, includes specific provisions regarding the Main Wheel Assembly (AD/F100/12). These provisions pertain to Fokker F28 Mk.0100 aircraft with ABS Corporation Main Wheel Assembly P/N 5008142-4, serial numbers APR91-0570 through FEB93-0965. The directive requires the identification and inspection of the Demountable Flange (inboard) and (outboard) Wheel Sub Assemblies, particularly focusing on those with specific part numbers and serial ranges. If damage or cracks are identified during inspection, the affected assembly must be replaced before any further flight. Additionally, repairs must be made in accordance with specified service bulletins from ABS Corporation.
Operators and entities governed by these regulations must ensure that the wheel assemblies meet the outlined inspection and repair requirements. This involves determining the part numbers and serial numbers of the wheel sub assemblies, conducting inspections as specified in the ABS Corporation service bulletins, and replacing or repairing any damaged assemblies. Compliance with these requirements is mandatory within three months of the directive's effective date, with subsequent inspections scheduled at specific flight cycle intervals or during tyre changes. Operators must also adhere to ongoing inspection requirements as detailed in the applicable Component Maintenance Manual.
Failure to comply with the requirements of this Airworthiness Directive can lead to significant consequences. The AD outlines that any non-compliance with the inspection, repair, and replacement procedures can result in the aircraft being deemed unairworthy. This can lead to enforcement actions by the Civil Aviation Safety Authority (CASA), including fines and potential criminal charges. The specific penalties for non-compliance are not detailed in the directive, but they can include substantial fines and legal repercussions for individuals and entities found in breach of the regulations. The directive underscores the importance of strict adherence to the outlined procedures to ensure the continued airworthiness and safety of the affected Fokker F100 aircraft.