COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Robin Aviation Series Aeroplanes
AD/ROBIN/21
Amdt 1
Stabilator Spar and Attachment Brackets 8/95
Applicability: All Models R2000 series.
Requirement: 1. Visually inspect, with the aid of strong lighting, the forward face of the rear fuselage bulkhead, which supports the stabilator hinge brackets. Look for cracks and corrosion. Pay particular attention to the area outboard of the stabilator hinge bracket bolt holes and around the stabilator balance weight cutout.
2. Remove the stabilator from the aircraft, in accordance with the Avions Pierre Robin R 2000 Service Manual Para 4.4.1, then:
remove the stabilator hinge brackets from the stabilator spar.
Inspect around the bolt holes and nut plate rivets in the stabilator spar using the fluorescent dye penetrant method as per CAO 108.10; and,
remove the stabilator hinge brackets from the rear fuselage bulkhead. Inspect the forward and aft faces of the bulkhead, outboard of the hinge bracket bolt holes and around the balance weight cutout, using the fluorescent dye penetrant method as per CAO 108.10.
Compliance: 1. Inspect in accordance with Requirement 1 before 1000 hours time in service or before further flight after 22 February 1995, whichever occurs later. Re-inspect at intervals not to exceed 100 hours.
2. Inspect in accordance with Requirement 2 before 2000 hours time in service or before 25 hours time in service after 22 February 1995,whichever occurs later. Re- inspect at intervals not to exceed 750 hours.
This amendment is effective 20 July 1995.
Background: During a precautionary inspection, not required by the maintenance schedule, a number of cracks were found in the rear fuselage bulkhead. Removal of the stabilator to facilitate repair revealed widespread cracking of the bulkhead and cracking of the stabilator spar near the hinge bracket bolts. The structural integrity of the stabilator attachment is critical to flight safety.
This amendment includes repeat inspections of the stabilator spar. Laboratory examination of the cracked stabilator spar has indicated that the condition of the rear fuselage bulkhead cannot be used to gauge the condition of the stabilator spar. The fatigue cracks in the stabilator spar started from fretting damage due to free movement of the stabilator hinge fittings and the balance weight attachment fitting.
Overview
The Civil Aviation Regulations 1998, specifically under Part 39 - 105, provides regulations to ensure the safety of civil aviation in Australia. Enacted by the Commonwealth of Australia, this legislation was introduced to address specific safety concerns related to the stabilator spar and attachment brackets in Robin Aviation Series Aeroplanes. The problem it targets is the structural integrity of the stabilator attachment, which is crucial for flight safety. The policy objective outlined in the regulation is to ensure the safety of aircraft by mandating specific inspections and maintenance procedures to prevent potential failures due to fatigue cracks and fretting damage. This is particularly important for the R2000 series models, where previous inspections have revealed critical issues with the rear fuselage bulkhead and stabilator spar, necessitating stringent oversight and regular checks to maintain airworthiness.
Scope and Application
The Civil Aviation Regulations 1998, as amended through the Legislative Instrument F2006B06619, specifically pertain to all Robin Aviation R2000 series models. These regulations mandate stringent safety inspections for critical structural components of the aircraft to ensure continued airworthiness. The directive, AD/ROBIN/21Amdt 1, mandates a detailed visual inspection of the rear fuselage bulkhead for signs of cracks and corrosion, particularly around areas subjected to high stress such as the stabilator hinge bracket bolt holes and the balance weight cutout. Additionally, the stabilator spar, which supports the stabilator, must be removed and inspected using the fluorescent dye penetrant method to detect any cracks that may not be visible to the naked eye. This amendment applies to all R2000 series models and requires initial inspections before specific time thresholds post-service hours or flight hours after 22 February 1995, with subsequent re-inspections at defined intervals. This regulation underscores the importance of maintaining the structural integrity of the stabilator attachment to ensure flight safety. The applicability of these regulations is overseen by the Civil Aviation Safety Authority (CASA) and extends across the Commonwealth of Australia, ensuring uniform compliance and safety standards.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, under the Civil Aviation Safety Authority's (CASA) Schedule of Airworthiness Directives, includes AD/ROBIN/21 Amendment 1, which mandates detailed inspection and maintenance procedures for the stabilator spar and attachment brackets of Robin Aviation Series R2000 aeroplanes. The directive applies to all R2000 models (Section 1). The primary requirement (Section 1.1) involves visually inspecting the forward face of the rear fuselage bulkhead for cracks and corrosion, with special attention to areas around the stabilator hinge bracket bolt holes and the stabilator balance weight cutout. Additionally, the stabilator must be removed to inspect the hinge brackets and spar using the fluorescent dye penetrant method as per CAO 108.10 (Section 1.2).
Compliance with these directives imposes obligations on aircraft operators and maintenance personnel. They must conduct the initial inspection before 1000 hours of time in service or before further flight after 22 February 1995, whichever is later, and repeat this inspection at intervals not exceeding 100 hours (Section 1.1). For the stabilator spar, the inspection must occur before 2000 hours of time in service or before 25 hours of time in service after 22 February 1995, whichever is later, with re-inspections at intervals not exceeding 750 hours (Section 1.2). These inspections are crucial for maintaining the structural integrity of the stabilator attachment, which is vital for flight safety.
Failure to comply with these airworthiness directives can lead to serious consequences. Non-compliance may result in potential safety hazards, such as structural failure during flight, which could lead to accidents. While the specific penalties are not outlined in this directive, general provisions under the Civil Aviation Act 1988 can impose civil penalties for non-compliance with airworthiness directives, which can include substantial fines and potential criminal charges for operators or maintenance personnel found negligent. The safety of passengers and crew, as well as the overall integrity of the aviation system, is paramount, and strict adherence to these inspection requirements is mandated to prevent any adverse incidents.