Overview

The Civil Aviation Safety Authority issued Airworthiness Directive AD/LJ60/2 under subregulation 39.1(1) of the Civil Aviation Safety Regulations 1998. The directive applies to Learjet 60 series aeroplanes with serial numbers 60-001 to 60-145. The directive was issued to address the unsafe condition of fuel crossflow tubes in certain Learjet 60 aeroplanes that could result in fuel loss during cross-feeding operations. The directive requires the inspection or replacement of the fuel crossflow tube with part number 6026020-005 and ensures that the clearance between the tube and flight control cables is at least 0.35 inch. If the clearance is less than 0.35 inch, a repair must be made before further flight. The directive became effective on 15 April 2004 and was notified in the Commonwealth of Australia Gazette on 24 March 2004.

Scope and Application

The Airworthiness Directive issued by the Civil Aviation Safety Authority (CASA) applies specifically to Learjet Model 60 aeroplanes with serial numbers ranging from 60-001 to 60-145 inclusive. This directive is a legislative instrument under subregulation 39.1 (1) of the Civil Aviation Safety Regulations 1998, establishing requirements for maintaining airworthiness standards for these aircraft. The directive mandates inspections and potential replacements of fuel crossflow tubes to ensure they meet specific clearance criteria relative to flight control cables, aiming to prevent fuel chafing and potential loss of fuel during cross-feeding operations. Compliance with the directive is mandatory for all aircraft within the specified serial number range, with different timeframes set for the various requirements, ensuring that the necessary actions are taken within specified periods post the directive's effective date of 15 April 2004. The directive's scope is nationwide, covering all Learjet 60 series aeroplanes operating within Australia, and it does not include any stated exemptions or exclusions.

Key Provisions

The main operative sections of this Airworthiness Directive (AD) revolve around the inspection and potential replacement of fuel crossflow tubes in specific Learjet 60 series aeroplanes. According to section (a) of the applicability, the directive applies to Learjet Model 60 aeroplanes with serial numbers (S/N) ranging from 60-001 to 60-145 inclusive. Section (b) of the requirement mandates that operators inspect the fuel crossflow tube or review aeroplane records to determine whether part number (P/N) 6026020-005 is installed. If this part number is found installed, the clearance between the fuel crossflow tube and the flight control cables must be measured to ensure it is at least 0.35 inches, as per the instructions in the Accomplishment Instructions of Bombardier Alert Service Bulletin A60-28-3, Revision 2. If the part number is not installed, it must be replaced with a new fuel crossflow tube having P/N 6026020-005, and the clearance must be measured according to the instructions in Bombardier Service Bulletin 60-28-4, Revision 2 or A60-28-3, Revision 2, depending on the aeroplane's serial number. If the clearance is found to be 0.35 inches or more, no further action is required. However, if the clearance is less than 0.35 inches, the tubes must be repaired using an approved method. The obligations and requirements imposed by this AD on the parties it governs are quite specific. Operators of the specified Learjet 60 series aeroplanes must ensure that within 25 flight hours after the effective date of this Directive, they inspect the fuel crossflow tube or review aeroplane records to determine if P/N 6026020-005 is installed (Requirement 1). Once this inspection is completed, they must follow up within 90 days by measuring the clearance between the fuel crossflow tube and the flight control cables (Requirement 2). If the part number is not installed, they must replace the existing tube with a new one having P/N 6026020-005 and measure the clearance again (Requirement 3). Any repairs necessary due to insufficient clearance must be completed before further flight (Requirement 5). Additionally, only fuel crossflow tubes with P/N 6026020-005 must be installed from the effective date of the Directive (Requirement 6). Failure to comply with the AD can result in severe consequences. While the legislation does not explicitly detail the penalties for non-compliance, it is reasonable to infer that non-compliance with ADs issued by the Civil Aviation Safety Authority (CASA) could lead to significant civil and criminal penalties. Non-compliance with ADs is generally considered a breach of civil aviation regulations, which can result in fines and other enforcement actions by CASA. Furthermore, if non-compliance leads to an unsafe condition that results in an accident or incident, it could lead to criminal charges against the operator or relevant parties, potentially resulting in imprisonment. The exact penalties would be determined based on the specific circumstances of the breach and the resultant impact on aviation safety.