AD/G1159/37 - Wing Plank Splice Between BL 135 and BL 156

Overview

The Civil Aviation Regulations 1998, established by the Australian Parliament, aim to ensure the safety and efficiency of civil aviation operations. Specifically, Part 39 - 105 of these regulations addresses the issuance of airworthiness directives, which are mandatory orders issued by the Civil Aviation Safety Authority to ensure the continued airworthiness of aircraft. The directive AD/G1159/37, introduced in response to reports of cracks in the wing plank splices of Gulfstream G1159 and G-IV series aeroplanes, was designed to enhance safety by mandating inspections and necessary repairs or replacements of the affected components. This directive seeks to prevent potential failures by requiring regular inspections and timely maintenance actions to ensure that the specified aircraft continue to meet the required safety standards.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 under the Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to all model GII, GIIB, and GIII Gulfstream (Grumman) aircraft. This regulation mandates a detailed inspection of the wing plank splice fail-safe channels and splice fittings on the lower middle and aft wing plank splices between BL 135 and BL 156 to detect any cracks. The inspection must be performed in accordance with specific Gulfstream Customer Bulletins (GCB) relevant to each model: GCB 400A for GII aircraft, GCB 403A for GIIB aircraft, and GCB 114A for GIII aircraft. Compliance with these regulations is required unless the inspection has already been completed, and it must be carried out within 150 flight hours or 90 days from 18 August 1994, whichever comes first. For aircraft found to have cracks within the specified limits and conditions, a re-inspection must occur at intervals not exceeding six months until the cracks are repaired or the wing plank replaced, which must be completed by the next regularly scheduled 18-month wing tank interior inspection. Subsequent inspections should then follow the Maintenance Manual requirements for this area. This directive is a response to reports of cracks in the specified areas of several GII and GIII aircraft, necessitating additional eddy current inspections if cracks are detected using the original ultrasonic inspection method.

Key Provisions

The primary operative sections of the Civil Aviation Regulations 1998, specifically Part 39 - 105, mandate that all Gulfstream G1159 and G-IV Series Aeroplanes undergo a specific inspection of the wing plank splice between BL 135 and BL 156 (Section 1). This inspection is required to detect any cracks in the fail-safe channels and splice fittings on the lower middle and aft wing plank splices. The inspection must be conducted in accordance with Gulfstream Customer Bulletins 400A, 403A, or 114A for model GII, GIIB, and GIII aircraft respectively. This directive was issued due to reports of cracks in these areas, which extend beyond the limits of detection specified in the original ultrasonic inspections. The Act imposes specific obligations on the parties involved. Owners and operators of the applicable Gulfstream aircraft must ensure that the specified inspections are conducted in a timely manner. If the aircraft has not been inspected within the required period, the inspection must occur within 150 flight hours or 90 days from 18 August 1994, whichever comes first (Section 2). If any cracks are found within the specified limits and conditions, the aircraft must be re-inspected at intervals not exceeding six months until the cracks are repaired or the affected parts replaced. These repairs or replacements must be completed by the next regularly scheduled 18-month wing tank interior inspection (Section 3). After this point, inspections must adhere to the requirements outlined in the Maintenance Manual. Failure to comply with the inspection requirements and timelines stipulated by the Civil Aviation Regulations 1998 may result in civil or criminal consequences. The severity of the penalties depends on the extent of non-compliance and the potential safety risks posed by the non-compliance. Although the specific penalties are not detailed in the provided text, it is reasonable to infer that non-compliance with safety directives of this nature could lead to significant civil penalties, including fines or other regulatory sanctions. In more severe cases, criminal charges could also be applicable, depending on the circumstances and the discretion of the court. The potential for such consequences underscores the importance of adhering to the regulations to ensure the safety and airworthiness of the aircraft.