COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Gulfstream (Rockwell) 112 Series Aeroplanes
AD/AC-112/15 Rudder Spar 6/95
Applicability: Models 112 and 112B aircraft with serial numbers 13000 and 3 to 544, inclusive.
Models 112TC and 112TCA aircraft with serial numbers 13001 to 13309, inclusive.
Requirement: 1. Visually inspect the rudder spar near the upper hinge fitting for signs of cracking. Check for excessive movement by attempting to move the rudder tip fore and aft and left to right.
2 (a). Remove the rudder assembly from the aircraft as outlined in the Maintenance Manual, Section VII. Remove the rudder tip assembly and the upper hinge fitting. Inspect the forward face of the rudder spar web, bend radius, flanges and angle doublers P/N 44006-RE3, if installed, for cracks in the area of the upper hinge fitting attachment. Inspect using the dye penetrant method in accordance with Rockwell Service Letter SL-112-46 and CAO 108.10.
Cracks, including stop drilled cracks, which extend beyond installed angle doublers, P/N 44006-RE3, must be repaired by replacement of the rudder spar before further flight.
2 (b). Modify the rudder spar upper hinge attachment area by installing angle doublers P/N 44006-RE3 in accordance with Rockwell SL-112-46, Figure 1. The rudder spar must be free of cracks before modification.
Any spar with angle doublers installed shall be regarded as cracked unless it can be positively confirmed that the rudder spar was crack free when the angle doublers were installed.
Compliance: 1. Inspect in accordance with Requirement 1 within 10 hours’ time in service after 25 May 1995.
2. Initially inspect in accordance with Requirement 2(a) before 100 hours’ time in service after 25 May 1995. Re-inspect at intervals not to exceed 200 hours’ time in service until modified in accordance with Requirement 2(b).
Background: The Authority has received reports of cracking of the rudder spar on a model 114 in the region of the upper hinge fitting. Substantial cracking was found on one aircraft 1500 hours’ time in service after compliance with AD/ROCK-114/10 with no defects found. The rudder structure on the model 112 is of similar design. This Directive requires repeat inspections of the hinge fitting area until the rudder spar is modified to the later production standard.
Overview
The Civil Aviation Regulations 1998 were enacted to regulate civil aviation in Australia, ensuring the safety and efficiency of air travel. The Civil Aviation (Safety) Regulations 1998, specifically Part 39 - 105, addresses the problem of rudder spar cracking in certain Gulfstream (Rockwell) 112 Series aeroplanes by issuing Airworthiness Directives. This legislative instrument was issued by the Civil Aviation Safety Authority to enhance aviation safety by providing specific maintenance and inspection requirements for the affected aircraft models. The policy objective is to mitigate the risk of structural failure by requiring regular inspections and necessary repairs to prevent further cracking and potential safety incidents.
The Airworthiness Directive AD/AC-112/15 focuses on the rudder spar of specified Gulfstream 112 Series aeroplanes, mandating visual and detailed inspections to detect and address any signs of cracking. Compliance with these directives is critical to ensure that the affected aircraft remain airworthy, thereby safeguarding passengers and crew. The regulations aim to preemptively address structural integrity issues, thereby maintaining high safety standards in civil aviation.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the safety directives applicable to certain Gulfstream (Rockwell) 112 Series Aeroplanes, focusing on the rudder spar. The directive applies to Model 112 and 112B aircraft with serial numbers ranging from 13000 to 544, and Models 112TC and 112TCA aircraft with serial numbers from 13001 to 13309. The requirement is for these aircraft to undergo a visual inspection of the rudder spar near the upper hinge fitting for signs of cracking, and to check for excessive movement by moving the rudder tip in various directions. Additionally, the rudder assembly must be removed, and the spar must be inspected for cracks using the dye penetrant method, in accordance with specified service letters and operational standards. Any cracks extending beyond the installed angle doublers must be repaired by replacing the rudder spar before further flight. Compliance mandates an initial inspection within 10 hours of time in service after 25 May 1995, followed by further inspections at intervals not exceeding 200 hours until the rudder spar is modified in line with the specified requirements. This directive is a response to reported instances of rudder spar cracking and aims to ensure ongoing safety by enforcing regular inspections and necessary modifications.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, contain the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, including AD/AC-112/15 which pertains to the rudder spar of Gulfstream (Rockwell) 112 Series aeroplanes. This directive applies to Models 112 and 112B with serial numbers 13000 to 3 to 544, inclusive, as well as Models 112TC and 112TCA with serial numbers 13001 to 13309, inclusive (Section 1). The directive mandates two main requirements. Firstly, the rudder spar near the upper hinge fitting must be visually inspected for signs of cracking, and the rudder tip must be checked for excessive movement (Section 1, Requirement 1). Secondly, the rudder assembly must be removed from the aircraft and further detailed inspections must be conducted, with any cracks found beyond installed angle doublers requiring the replacement of the rudder spar (Section 1, Requirement 2(a)). Additionally, the rudder spar must be modified by installing angle doublers P/N 44006-RE3 as per Rockwell Service Letter SL-112-46 (Section 1, Requirement 2(b)).
The obligations imposed by this directive on the relevant parties, such as aircraft operators and maintenance personnel, include ensuring that the specified inspections and modifications are carried out in accordance with the outlined procedures and timeframes. Specifically, the initial inspection as per Requirement 1 must be completed within 10 hours of time in service after 25 May 1995 (Section 1, Compliance 1). The inspection and possible modification as per Requirement 2(a) must occur before 100 hours of time in service after 25 May 1995, with re-inspections at intervals not exceeding 200 hours of time in service until the rudder spar is modified in accordance with Requirement 2(b) (Section 1, Compliance 2).
Failure to comply with the requirements set forth in this directive may lead to serious safety implications, potentially resulting in civil or criminal penalties. The exact consequences for non-compliance are not specified within the text of the directive itself, but under Australian aviation law, non-compliance with airworthiness directives can result in penalties including fines and imprisonment. The severity of the penalties would depend on the specific breach and the discretion of the court.