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/F100/18 MLG Sliding Member Wheel Axle 4/99
Applicability: F.28 Mk.0100 aircraft, all serial numbers, if equipped with Dowty Main Landing Gear Part Number (P/N) 201072011, 201072012, 201072013, 201072014,
201072015, or 201072016.
Requirement: Accomplish either one of the following:
- Visually inspect the sliding members of all affected main landing gears installed on in-service aircraft for the presence of corrosion on the wheel axles in accordance with Fokker Service Bulletin (SB) F100-32-080, dated 4 October 1993, and in accordance with Dowty Aerospace SB F100-32-64, dated 23 September 1993; or,
2. Rework the axles in accordance with paragraph 2.B Part B of Dowty Aerospace SB F100-32-64 Revision 1 dated 18 February 1994; prior to, or at the same time of the rework of the axles, the main wheel brake units must be replaced in accordance with ABS Corporation SB Fo-100-57 Revision 1.
Note 1: Aircraft that were on a sampling program (which expired on 1 January 1999) in conjunction with Requirement 2 actions in accordance with Fokker SF F100-32-083, are now required to introduce the Requirement 1 inspections.
If corrosion is found during the Requirement 1 inspection, before further flight, rework the affected area and perform a Non-Destructive Testing (NDT) inspection for cracks in accordance with Appendix A of Dowty Aerospace SB F100-32-63 dated
29 July 1993, or in accordance with Appendix A of Dowty Aerospace SB F100-32-64 dated 23 September 1993.
Note 2: The rework specified in the paragraph immediately above does not constitute terminating action for the Requirement 1 repetitive inspection requirement.
If cracks are detected during any inspection required by this Directive, before further flight, replace the affected sliding member with a serviceable part in accordance with applicable maintenance procedures.
Note 3: Replacement of the sliding member does not constitute terminating action for the repetitive inspection requirements of Requirement 1 of this Directive, unless the replacement part is in post Fokker SB F100-32-081 configuration.
Note 4: RLD BLA 93-108/3(A) refers.
Compliance: 1. Within three calendar months after the last inspection, or one calendar month after 22 April 1999, whichever occurs later; thereafter at intervals not to exceed three calendar months, until the requirements specified in the compliance note below are met.
COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
2. If Requirement 2 has been accomplished, introduce the Requirement 1 repetitive inspections within one calendar month after 22 April 1999, and thereafter at intervals not to exceed three calendar months until the requirements specified in the compliance note below are met.
Note: After the replacement of main wheel brake units in accordance with ABS Corporation SB Fo100-32-57, Revision 1 dated 2 February 1994; and rework of the sliding member in accordance with paragraph 2.C PART C of Dowty Aerospace SB F100-32-64, Revision 1, the Requirement 1 repetitive inspections are no longer required.
This Airworthiness Directive becomes effective on 22 April 1999.
Background: An F.28 Mk.0100 operator reported the occurrence of an incident where, during push- back of the aircraft, a MLG wheel axle failed. Subsequent investigation revealed the presence of corrosion on most wheel axles in service with this operator. Preliminary results indicate that the crack which led to the failed axle had initiated from a corrosion pit located on the radius of the brake abutment flange on the axle.
Overview
The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority (CASA), were enacted to ensure the safety of civil aviation in Australia. The Regulations aim to maintain a high standard of safety in civil aviation by setting forth comprehensive rules and directives. Part 39, in particular, addresses airworthiness directives that are crucial for ensuring the ongoing safety of aircraft. One such directive, AD/F100/18, focuses on the Fokker F100 (F28 Mk 100) Series Aeroplanes, specifically addressing corrosion issues with the Main Landing Gear (MLG) sliding member wheel axles. This directive was introduced to mitigate the risk of wheel axle failure due to corrosion, which could potentially lead to catastrophic outcomes. The directive mandates either visual inspections for corrosion or the reworking of the axles, followed by the replacement of the main wheel brake units. Compliance with these requirements is crucial to ensure that affected aircraft remain airworthy and safe for operation.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, encompasses a schedule of airworthiness directives that are binding for particular aircraft and their components. One such directive, AD/F100/18, applies to Fokker F100 (F28 Mk 100) series aeroplanes with specific Dowty Main Landing Gear part numbers, necessitating stringent inspection and maintenance procedures to ensure safety. This directive mandates that all F.28 Mk.0100 aircraft equipped with the specified Dowty Main Landing Gear parts must undergo visual inspections for corrosion on the wheel axles or rework the axles in accordance with prescribed service bulletins. Compliance with these requirements must be achieved within certain timeframes post the directive's effective date, with subsequent inspections at intervals not exceeding three months. This regulatory framework ensures the ongoing airworthiness of the aircraft by addressing potential structural integrity issues proactively.
Key Provisions
The Civil Aviation Regulations 1998 (section 39-105) outline specific airworthiness directives for Fokker F100 (F28 Mk 100) series aeroplanes, particularly focusing on the maintenance of the Main Landing Gear (MLG) sliding member wheel axles. This directive applies to F.28 Mk.0100 aircraft equipped with Dowty Main Landing Gear Part Numbers 201072011 through 201072016. The primary requirement is to either visually inspect the sliding members for corrosion on the wheel axles in accordance with Fokker Service Bulletin F100-32-080 (section 4/99) or rework the axles in accordance with Dowty Aerospace Service Bulletin F100-32-64 Revision 1 (section 2.B Part B), while simultaneously replacing the main wheel brake units as specified in ABS Corporation Service Bulletin Fo-100-57 Revision 1. Aircraft that were previously on a sampling program must now conduct the inspections as per Requirement 1. If corrosion is detected, the affected area must be reworked and Non-Destructive Testing (NDT) conducted for cracks in accordance with Dowty Aerospace Service Bulletins F100-32-63 or F100-32-64 (Appendix A). Should cracks be found, the sliding member must be replaced with a serviceable part. It is important to note that replacement of the sliding member does not terminate the repetitive inspection requirements unless the part is in post Fokker SB F100-32-081 configuration.
The Civil Aviation Regulations impose specific obligations on the operators and maintenance personnel of the affected Fokker F100 aircraft. They must comply with the inspection and rework requirements as stipulated by the airworthiness directive. Operators must conduct visual inspections for corrosion or undertake the necessary rework of the wheel axles, ensuring that the main wheel brake units are also replaced accordingly. Should corrosion or cracks be found during any inspection, the appropriate corrective actions must be taken before further flights. Operators must adhere to the compliance timeframes, performing the inspections within three months after the last inspection or within one month after 22 April 1999, whichever is later, and then at intervals not exceeding three months. If rework has been performed in accordance with the specified service bulletins, repetitive inspections are no longer required.
Breach of the airworthiness directive's requirements can lead to serious safety implications and potential legal consequences. Non-compliance with the inspection and rework mandates can result in the continued operation of aircraft with potentially unsafe conditions, leading to severe risks during flight. The Civil Aviation Safety Authority (CASA) may impose penalties for non-compliance, which can include fines and other enforcement actions. While the specific maximum penalties are not detailed within the directive, they are typically set out in other sections of the Civil Aviation Regulations or associated legislation, and can vary depending on the severity and circumstances of the breach. Operators and maintenance personnel must ensure strict adherence to the stipulated requirements to avoid these repercussions.