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.
Boeing 767 Series Aeroplanes
AD/B767/173 Thrust Reverser Directional Pilot Valve 7/2002
DM
Applicability: Model 767 series aeroplanes with General Electric CF6-80C2 series engines.
Requirement: 1. (a) For aeroplanes not modified in accordance with Boeing Service Bulletin (SB) 767-78-0063 or production equivalent carry out and successfully accomplish a functional test of the Directional Pilot Valve (DPV) of the thrust reversers to detect pneumatic leakage in accordance with Boeing Alert SB 767-78-0084 dated 21 October 1999.
(b) For aeroplanes modified in accordance with Boeing SB 767-78-0063 or production equivalent carry out and successfully accomplish a functional test of the DPV of the thrust reversers to detect pneumatic leakage in accordance with Boeing Alert SB 767-78-0084 dated 21 October 1999.
2. Repeat and successfully accomplish a functiona l test of Requirement 1(a).
3. Repeat and successfully accomplish a functional test of Requirement 1(b).
4. If any functional test required by Requirement 1, 2 or 3 of this Directive cannot be successfully carried out in accordance with the reference service bulletin, or if any discrepancy is detected during any functional test, repair in accordance with the Aircraft Maintenance Manual.
5. Repeat Requirement 1 functional tests if any discrepancies have been corrected under Requirement 4 during compliance with requirement 1, 2 or 3.
Production Equivalent
Functional tests accomplished in accordance with a production equivalent for aeroplanes modified during production, are acceptable as equivalent to the initial functional test required by Requirement 1(b) of this Directive. Therefore, in this case, compliance with Requirement 1(b) is not necessary.
Note: FAA AD 2000-17-06 Amdt 39-11880 refers.
Boeing 767 Series Aeroplanes
AD/B767/173 (continued)
Compliance: For Requirement 1: (a) Within 30 days after the effective date of this Directive.
(b) With the exception of aeroplanes modified and functionally tested in accordance with a production equivalent, within 60 days after the effective date of this Directive.
For Requirement 2: At intervals not exceeding 1,000 flight hours. For Requirement 3: At intervals not exceeding 6,000 flight hours. For Requirement 4: Prior to further flight.
For Requirement 5: Prior to further flight.
This Airworthiness Directive becomes effective on 5 June 2002.
Background: A possible leakage of the thrust reverser Directional Pilot Valve (DPV), due to a poppet valve being slightly jammed open or a leaking o-ring, has been identified by a report to the FAA as a latent failure of the fail-safe features of the thrust reverser system. The actions specified in this Directive are intended to ensure the integrity of the fail-safe features by preventing possible failure modes that could result in inadvertent deployment of the thrust reverser in- flight.
James Coyne
Delegate of the Civil Aviation Safety Authority 28 May 2002
The above AD is notified in the Commonwealth of Australia Gazette on 5 June 2002.
Overview
The Airworthiness Directive (AD) AD/B767/173 was enacted in 2002 by the Civil Aviation Safety Authority (CASA) to address a potential safety issue identified in Boeing 767 series aeroplanes with General Electric CF6-80C2 series engines. This issue involved the possible leakage of the thrust reverser Directional Pilot Valve (DPV) due to a poppet valve being slightly jammed open or a leaking o-ring, which could compromise the fail-safe features of the thrust reverser system and lead to inadvertent deployment during flight. The AD mandates functional tests of the DPV to detect pneumatic leakage, and if any discrepancies are detected, requires repairs as per the Aircraft Maintenance Manual. The policy objective of this directive is to ensure the safety and airworthiness of the specified aircraft by preventing potential failure modes of the thrust reverser system.
Scope and Application
This Airworthiness Directive applies to Boeing 767 series aeroplanes equipped with General Electric CF6-80C2 series engines, encompassing both modified and unmodified aircraft. The directive, issued under the authority of the Civil Aviation Safety Authority (CASA) delegate, mandates specific actions to ensure the safety of the aircraft by addressing a potential unsafe condition related to the thrust reverser Directional Pilot Valve (DPV). The directive requires functional tests to detect pneumatic leakage and mandates repairs if any discrepancies are found during these tests. The AD outlines specific timeframes for compliance, such as within 30 or 60 days from the directive's effective date, and at regular intervals not exceeding 1,000 or 6,000 flight hours, depending on the requirement. Additionally, if any discrepancies are corrected, certain functional tests must be repeated before further flight. This directive is applicable across the Commonwealth of Australia and extends to all relevant aircraft within its jurisdiction, with no stated exclusions or exemptions.
Key Provisions
The Airworthiness Directive (AD) issued under subregulation 39.1 (1) of the Civil Aviation Regulations 1998, pertains to Boeing 767 series aeroplanes equipped with General Electric CF6-80C2 series engines. The directive specifically addresses potential issues with the thrust reverser Directional Pilot Valve (DPV), which could lead to a pneumatic leakage and compromise the fail-safe features of the thrust reverser system. The AD requires certain actions to be taken to ensure the safety and airworthiness of these aeroplanes. Firstly, operators must carry out functional tests of the DPV to detect any pneumatic leakage in accordance with Boeing Alert SB 767-78-0084 dated 21 October 1999. The testing regime is slightly different for aeroplanes that have been modified in accordance with Boeing Service Bulletin (SB) 767-78-0063 or production equivalent.
The obligations under this AD include conducting the specified functional tests within certain timeframes. For aeroplanes not modified in accordance with Boeing SB 767-78-0063, the initial functional test must be completed within 30 days of the AD's effective date. For those modified and functionally tested during production, this test is not necessary. The functional tests must then be repeated at intervals not exceeding 1,000 flight hours and 6,000 flight hours, as stipulated in the AD. If any discrepancies are detected during these tests, repairs must be carried out in accordance with the Aircraft Maintenance Manual, and the tests must be repeated before further flight. Production equivalent functional tests are acceptable as equivalent to the initial test.
Failure to comply with this AD can result in significant consequences. While the AD itself does not explicitly state penalties, non-compliance with airworthiness directives issued under the Civil Aviation Regulations 1998 can lead to enforcement actions by the Civil Aviation Safety Authority (CASA). Such actions can include fines, suspension or revocation of air operator certificates, and potential criminal charges in cases of gross negligence or willful disregard of safety regulations. The severity of the penalties depends on the nature and extent of the non-compliance, and CASA has the authority to take appropriate action to ensure compliance with aviation safety standards.