AD/GAZELLE/8 - Non Rotating Scissors Attach Bolt - Replacement

The instrument directly affects owners and operators of Eurocopter SA341 and SA342 Gazelle series helicopters fitted with main rotor head part number 341A.31.0001 or 341A.31.0020 in any dash number, provided modification AMS 07.6129 has not been incorporated. Maintenance organisations responsible for the continuing airworthiness of these aircraft are also affected, as they must ensure the replacement action is performed and documented. Pilots operating such aircraft must confirm that the compliance requirement has been met before flight, given the implications for the aircraft's airworthiness status.

The directive does not extend to helicopters that have incorporated modification AMS 07.6129 or to models fitted with different main rotor head part numbers. It therefore creates a defined subset of the Gazelle fleet that remains subject to the replacement obligation. Compliance professionals advising on fleet management must identify affected aircraft by cross-referencing part numbers and modification records against the applicability statement.

The instrument imposes a duty on operators and maintainers to replace the non rotating scissors attach bolt and apply the revised torque within 100 hours time in service after 31 August 1979. This duty is tied to the procedures set out in Gazelle SB 01-18. Operators must ensure that the new bolt is installed and that the torque is adjusted to the revised figure to address the excessive wear identified in the background section.

The source text does not expressly confer additional rights beyond the ability to rely on the referenced service bulletin for implementation. Operators retain the right to operate the aircraft once the required replacement has been completed and recorded. There is no provision in the instrument for extensions of the compliance period or alternative methods of compliance. The duty to comply is absolute for aircraft falling within the applicability criteria.

The source text does not specify penalties or detailed enforcement mechanisms for non-compliance with AD/GAZELLE/8. As a legislative instrument made under the Civil Aviation Regulations 1998, Part 39, and forming part of the Schedule of Airworthiness Directives, failure to complete the required bolt replacement may result in the aircraft being considered unairworthy. The Civil Aviation Safety Authority retains authority to take administrative action, including grounding affected aircraft or requiring rectification before further flight.

Related provisions on legislative instruments indicate that such directives are subject to construction rules that treat them as subordinate to the enabling legislation. This means enforcement actions must align with the broader civil aviation regulatory framework rather than creating standalone penalty provisions within the directive itself. No specific offences or monetary penalties are detailed in the text of AD/GAZELLE/8.

This instrument interacts with the Civil Aviation Regulations 1998, Part 39, under which the Schedule of Airworthiness Directives is maintained. It is a legislative instrument for the purposes of the Legislation Act 2003, as it is made under a power delegated by Parliament that determines the law by imposing specific airworthiness requirements on particular aircraft. Section 7 of the Legislation Act 2003 outlines that instruments registered on the Federal Register of Legislation or made under delegated powers that alter the content of the law qualify as legislative instruments.

Section 13 of the Legislation Act 2003 governs the construction of the instrument. The Acts Interpretation Act 1901 applies to the directive as if it were an Act, expressions used in the instrument have the same meaning as in the enabling legislation, and the instrument must be read subject to the enabling legislation as in force from time to time. This ensures that terms such as "time in service" and "modification" are interpreted consistently with the Civil Aviation Regulations 1998.

The instrument does not fall within the exclusions in section 54 of the Legislation Act 2003, as it is not an instrument facilitating an intergovernmental body or scheme, nor is it one to which the Part is stated not to apply by an Act. It therefore remains fully subject to the registration, publication and construction requirements applicable to legislative instruments.

The source text of AD/GAZELLE/8 is dated 7/79 and contains no indication of subsequent amendments or revisions. The instrument therefore remains in the form originally issued, with the compliance requirement fixed at 100 hours time in service after 31 August 1979. No updates to the applicability criteria, torque specifications or referenced service bulletin are recorded in the provided text.

The absence of changes reflects the targeted and time-limited nature of the directive, which addressed a specific wear issue identified in the background section. The original torque specification was determined to be too low, leading to the need for a new bolt and revised torque figure. Because the compliance window is historical, the instrument has not required updating in the source material to reflect ongoing fleet modifications or new service bulletins.

The source text does not record any court challenges, legal proceedings or controversies associated with AD/GAZELLE/8. No cases are named in the instrument or in the related retrieval context concerning this particular directive. The instrument's narrow focus on a single component replacement for a defined subset of Gazelle helicopters has not generated documented disputes in the provided material.

The absence of challenges in the source text means that questions of validity, interpretation or enforcement have not been tested through judicial proceedings according to the available information. Practitioners must therefore rely on the plain wording of the applicability statement and compliance requirement when advising on the instrument's effect.

One potential issue arises from the need to accurately determine whether modification AMS 07.6129 has been incorporated on a particular aircraft. The instrument excludes helicopters that have this modification, so incorrect assessment of modification status could lead to unnecessary replacement or, conversely, failure to perform the required action on an applicable aircraft. Maintenance records must be examined carefully to confirm the presence or absence of the modification.

Another consideration is the calculation of the 100 hours time in service compliance window. The deadline is measured from 31 August 1979, meaning that for each aircraft the period during which the replacement must occur is fixed by its individual usage history. Operators must ensure that time in service is tracked precisely to avoid missing the deadline.

The requirement to install a new bolt and apply a revised torque figure, as detailed in Gazelle SB 01-18, introduces the need for verification that the correct replacement part is used and that the torque is set to the updated specification. Failure to follow the service bulletin procedures exactly could result in the wear issue not being fully resolved, even if a bolt replacement is attempted.

To comply with AD/GAZELLE/8, operators must first confirm that the helicopter is fitted with main rotor head part number 341A.31.0001 or 341A.31.0020 in any dash number and that modification AMS 07.6129 has not been incorporated. Once applicability is established, the non rotating scissors attach bolt must be replaced in accordance with the procedures in Gazelle SB 01-18. The new bolt must be installed and torqued to the revised figure specified in that service bulletin.

The replacement action must be completed within 100 hours time in service after 31 August 1979. Maintenance documentation should record the part number of the new bolt, the torque value applied, and the date and aircraft hours at which the work was performed. After completion, the aircraft may continue in service without further action under this directive, provided no other applicable requirements exist.

Practitioners advising clients should recommend a review of all maintenance records for affected Gazelle helicopters to verify compliance status. Where an aircraft has accumulated hours since 31 August 1979 without the replacement, immediate grounding and rectification may be necessary to restore airworthiness. The Civil Aviation Safety Authority should be consulted if there is uncertainty regarding the applicability of the instrument to a specific aircraft.