AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
Instruments and Automatic Pilots
AD/INST/48 Honeywell Inertial Reference Unit 9/2002
Applicability: Honeywell inertial reference units (IRU) with part number (P/N) HG1075AB05, any serial number (last four digits) 0644 through 0723 (excluding 0652 and 0659), that incorporates Modification 3 but not Modification 7; or
Honeywell IRU P/N HG1075GB05, with either serial number (last four digits) 0652 or 0659, that incorporates Modification 2 but not Modification 6.
Note 1: These IRUs are primarily on early manufactured Dassault Falcon Jets, but could be incorporated on other aircraft through either an STC or CAR (1988) 35 modification
Requirement: 1. Inspect any affected IRU for proper function in accordance with the instructions in Honeywell Alert Service Bulletin (ASB) HG1075AB-34-A0013, dated 21 May 2001; or Honeywell ASB HG1075GB-34-A0005, dated 21 May 2001, as applicable.
2. If, during the Requirement 1 inspection, the IRU does not function properly, remove the IRU from the aeroplane and return it to Honeywell for incorporation of Modification 6 or 7, as applicable.
3. If, during the Requirement 1 inspection, the IRU functions properly, remove the IRU from the aeroplane and return it to Honeywell for incorporation of Modification 6 or 7, as applicable.
4. IRUs identified in the applicability statement may not be installed in any aeroplane unless the IRU has been modified at Honeywell, Inc. and updated to one of the following:
IRU P/N HG1075AB05 IRU, to Mod 7, or IRU P/N HG1075GB05 IRU, to Mod 6.
Note 2: FAA AD 2002-13-07 Amdt 39-12795 refers.
Compliance: For Requirement 1 - Within the ne xt 50 hours time in service (TIS) after the effective date of this Directive.
For Requirement 2 - Prior to further flight after the Requirement 1 inspection.
Instruments and Automatic Pilots
AD/INST/48 (continued)
For Requirement 3 - Within 200 hours TIS after the Requirement 1 inspection. For Requirement 4 - As of the effective date of this Directive.
This Airworthiness Directive becomes effective on 5 September 2002.
Background: This Directive requires the inspection of affected IRUs for proper function and the removal of the IRU either immediately or within 200 hours TIS, depending on the result of the inspection. The Directive is the result of a report that these IRUs may not function when using backup battery power in certain installations. Failure of an IRU to transition to backup battery power could result in loss of attitude, heading, together with position reference and could lead to the pilot making flight decisions that put the aircraft in unsafe flight conditions.
Eugene Paul Holzapfel
Delegate of the Civil Aviation Safety Authority 29 July 2002
The above AD is notified in the Commonwealth of Australia Gazette on 14 August 2002.
Overview
The Airworthiness Directive (AD) 2002/48, issued under subregulation 39.1 (1) of the Civil Aviation Regulations 1998 (CAR 1998), targets specific Honeywell inertial reference units (IRU) used in aircraft to address safety concerns related to their operation on backup battery power. This AD was enacted to rectify a potentially unsafe condition identified in certain IRU models, which could fail to transition to backup power, leading to critical flight information loss and unsafe flight conditions. The directive was issued by the Civil Aviation Safety Authority (CASA) delegate, with a clear policy objective of enhancing aviation safety by ensuring the proper functionality of these critical components. The directive became effective on 5 September 2002, mandating inspections and necessary modifications to the specified IRUs to mitigate identified risks.
Scope and Application
The Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998 (CAR 1998) applies specifically to certain Honeywell inertial reference units (IRU) used in aircraft. The AD mandates that specified IRUs with particular part numbers and serial numbers, predominantly found on Dassault Falcon Jets but potentially on other aircraft through modifications, undergo specific inspections and modifications to ensure airworthiness. The directive applies to these units whether they are installed on aircraft in Australia or elsewhere, as they are subject to Australian aviation safety standards. The AD does not explicitly exclude any entities or specific industries, but its primary focus is on ensuring the safety of the identified IRUs within the Australian aviation sector. The AD sets out clear requirements for inspections and modifications, with strict timelines for compliance, and it extends its application through the issuance of specific instructions and deadlines. Any non-compliance with this AD could lead to the grounding of affected aircraft until the necessary actions are taken.
Key Provisions
The main operative sections of this Airworthiness Directive (AD) are contained in the requirement section (subregulation 39.1 (1) of CAR 1998) which mandates specific actions to address the identified unsafe condition. Requirement 1 demands that affected Honeywell Inertial Reference Units (IRU) be inspected for proper function in accordance with specified Honeywell Alert Service Bulletins (ASB). Requirement 2 and 3 stipulate that if the IRU does not function properly or functions properly, it must be removed from the aeroplane and returned to Honeywell for modification. Requirement 4 ensures that these IRUs can only be reinstalled in an aeroplane after they have been modified by Honeywell and updated to either Mod 6 or Mod 7, as applicable.
The AD imposes several obligations on the parties or entities it governs. Firstly, it mandates that all Honeywell IRUs identified in the applicability section be inspected within 50 hours of the AD's effective date. If an IRU is found to be non-functional, it must be removed and returned to Honeywell for modification prior to further flight. If the IRU is found to be functional, it must still be removed and returned to Honeywell within 200 hours of the inspection. The AD also specifies that modified IRUs must not be installed in any aeroplane until they have been updated to either Mod 6 or Mod 7, as applicable. These requirements are intended to ensure that all affected IRUs are properly maintained and modified to prevent unsafe flight conditions.
There are no explicit offences, penalties, or civil/criminal consequences mentioned within this AD. However, non-compliance with the requirements of this Airworthiness Directive could potentially lead to significant safety risks and violations of aviation regulations, which may result in enforcement actions by the Civil Aviation Safety Authority (CASA). The failure to adhere to the AD could lead to the grounding of affected aircraft until the required modifications are made, resulting in operational disruptions and potential financial losses for operators. Furthermore, continued operation of aircraft with non-compliant IRUs could expose operators to liability in the event of an accident or incident resulting from IRU failure.