AD/DHC-1/15 - Tail Landing Gear and Lower Surface of Tailplane - Inspection and Modification

Overview

The Civil Aviation Regulations 1998, specifically within Part 39 - 105 concerning the Civil Aviation Safety Authority Schedule of Airworthiness Directives, include AD/DHC-1/15 which pertains to De Havilland DHC-1 (Chipmunk) Series Aeroplanes. This directive was enacted to address the need for regular inspection and maintenance of the tail landing gear and lower surface of the tailplane to ensure the continued airworthiness and safety of these aircraft. The enacting body, the Civil Aviation Safety Authority, established these requirements to mitigate risks associated with structural integrity, particularly in the tailplane area, which is crucial for the stability and control of the aircraft during flight. The overarching policy objective is to ensure that Chipmunk aircraft remain safe and reliable, minimising the risk of accidents arising from mechanical failures in the tail section. The directive mandates specific inspections and, if necessary, modifications to the tail landing gear and the lower surface of the tailplane to prevent buckling and other damage. This involves inspecting the shock absorber attachment bracket and the bolts for security and wear. The compliance requirements specify detailed intervals for inspections, with more frequent checks for certain models to ensure that any issues are identified and addressed promptly. These measures aim to maintain the integrity of the aircraft's structural components, thereby enhancing overall flight safety.

Scope and Application

The Civil Aviation Regulations 1998, specifically PART 39 - 105, pertain to the requirements for maintaining the airworthiness of De Havilland DHC-1 (Chipmunk) series aeroplanes, as stipulated by the Civil Aviation Safety Authority. This legislation applies to all models of Chipmunk aeroplanes, mandating specific inspection and modification procedures to ensure safety and compliance with airworthiness standards. For model TMK 10 aircraft, inspections and repairs must adhere to Chipmunk Modification H.167, while other models should be repaired according to an approved repair scheme. The inspection frequency is set at intervals not exceeding 100 hours of time in service and after each heavy landing, with additional daily inspections required for unmodified TMK 10 aeroplanes. This legislation has a broad jurisdictional reach across the Commonwealth of Australia, enforcing compliance with the specified airworthiness directives for all Chipmunk series aeroplanes operating within Australian airspace. There are no stated exclusions or exemptions within the regulations, meaning all applicable aircraft must comply with the outlined inspection and modification procedures. The scope of application may be extended or restricted through subordinate instruments, although these are not detailed within the primary text of the regulation.

Key Provisions

The main operative sections of this legislation pertain to the inspection and modification requirements for the De Havilland DHC-1 (Chipmunk) Series Aeroplanes. According to section 1, the lower surface of the tailplane must be inspected for buckling and other damage in the vicinity of the shock absorber attachment bracket. Specifically, model TMK 10 aircraft that show any buckling or damage must be repaired and modified in accordance with Chipmunk Modification H.167. All other models must be repaired following an approved repair scheme (sections 1(a) and (b)). Additionally, the shock absorber upper attachment bracket must be inspected for security, elongation of bolt holes, and other damage, while the upper and lower attachment bolts must be inspected for excessive wear, cracks, evidence of shearing, and other damage (sections 2 and 3). The obligations imposed by this legislation require regular inspections and modifications to maintain the airworthiness of Chipmunk aeroplanes. For model TMK 10 aeroplanes not modified in accordance with Chipmunk Modification H.167, inspections must be carried out daily and after each heavy landing. For model TMK 10 aeroplanes modified in accordance with Chipmunk Modification H.167 and all other models, inspections must occur at intervals not exceeding 100 hours of time in service and after each heavy landing (section 1(a) and (b)). The shock absorber upper attachment bracket and the upper and lower attachment bolts must also be inspected at intervals not exceeding 100 hours of time in service and after each heavy landing (sections 2 and 3). Breach of these requirements could lead to severe consequences, including civil and criminal penalties. Although the specific penalties are not detailed within this legislative instrument, failure to comply with airworthiness directives can result in serious legal ramifications under broader civil aviation regulations. Non-compliance can lead to grounding of the aircraft, fines, and in severe cases, criminal charges against the responsible parties, including operators and maintenance personnel. The exact penalties would depend on the specific breach and the interpretation of the broader regulatory framework governing civil aviation in Australia.