ezap and ewis - aviation africa siasa... · siasa project this project is funded by the european...
TRANSCRIPT
SIASA project
This project is funded by the European Union and implemented by EASA.
TE.GEN.00409-001
EZAP and EWIS
Graeme Riddick Airworthiness Engineer Head of Structure and Systems installation certification Technology Evolution – Impact on Airworthiness 23-24 September 2014, Windhoek, Namibia
Ageing Aircraft - Wiring
CONTENTS
Historical background
Regulation status
Airbus implementation status
Enhanced logic – summary
A320 family EZAP implementation
Minimisation of maintenance burden
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 2
History
Safety concerns about wiring systems brought to public attention by a midair explosion in 1996 involving a B747-100 manufactured in July 1971
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 3
History
The NTSB conclusions included: Existing standards for wire separation may not provide adequate protection against damage from short circuits.
A short circuit producing excess voltage that was transferred to the center wing tank (CWT) fuel quantity indication system wiring is the most likely source of ignition energy for the CWT explosion.
The condition of the wiring system in the accident airplane was not atypical for an airplane of its age, and the airplane was maintained in accordance with prevailing accepted industry practices.
Until recently, insufficient attention has been paid to the condition of aircraft electrical wiring, resulting in potential safety hazards
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 4
History
In 1997 a White House commission requested FAA to expand their Aging Aircraft Program to include systems
FAA issued an Aging Systems Plan focussing, initially, on wiring systems. The Aging Transport Systems Rulemaking Advisory Committee (ATSRAC) was formed to provide FAA with advice and recommendations
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 5
History
An accident in September 1998 following an in-flight fire of an MD-11 manufactured in 1991
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 6
History
TSB Conclusions: A segment of in-flight entertainment network (IFEN) power supply unit cable (1-3791) exhibited a region of resolidified copper on one wire that was caused by an arcing event. This resolidified copper was determined to be located near manufacturing station 383, in the area where the fire most likely originated. This arc was likely associated with the fire initiation event; however, it could not be determined whether this arced wire was the lead event.
Examination of several MD-11 aircraft revealed various wiring discrepancies that had the potential to result in wire arcing. Other agencies have found similar discrepancies in other aircraft types. Such discrepancies reflect a shortfall within the aviation industry in wire installation, maintenance, and inspection procedures.
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 7
Regulation status
Aircraft ageing in general:
Introduction of a change to Part 21 to require TC and STC Holders to update their ICAs to take account of ageing aircraft/systems issues when they have been identified and agreed by the Agency.
EWIS NPA 2007-01 published in 2007 and adopted in 2008
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 8
Regulation status
Changes to CS 25
Introduction of a new subpart H
Including specific reference to ICA for:
Perform EZAP
Produce Electrical Standard Wire Practices Manual (ESWPM)
Wiring identification
Wiring separation
Electrical load analyses
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 9
Regulation status
Part M (Maintenance Requirements)
to require operators to include the output of EZAP into their maintenance programmes,
amend subpart D to reflect EWIS maintenance / inspection standards
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 10
Regulation status
Existing TC
Incorporation of a new CRI H-01 into existing TCDS
All changes to type design are now required to review the impact of the change on EWIS and update ICA when appropriate
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 11
Airbus is required Maintenance and inspection requirements for the EWIS developed with the use of an enhanced zonal analysis procedure (EZAP)
So what is EZAP?
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 12
Enhanced logic – summary
Primary concern is the potential fire hazard
EZAP must identify tasks to minimize this potential
Two approaches
Minimize occurrence of ignition source
Minimize consequences of ignition source
The results must be realistic and any new tasks must not increase potential for new discrepancies
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 13
Enhanced logic – summary
For each zone, application of the enhanced logic either:
Confirms that existing zonal inspection is adequate
or
Leads to identification of:
GVI (standalone) of some or all wiring in a zone
Detailed Inspections of some or all wiring in a zone
Restoration (cleaning) tasks to reduce likelihood of significant build-up of combustible materials
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 14
A320 EZAP Implementation
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 15
On-aircraft WG – Shannon, Ireland May 2005
A321-200 msn 1080 of DLH
8 operators – ANA, BAW, CIT, MON, NWA, SAS,TAP, UAL
3 Authorities – CAA, DGAC, FAA
111 dossiers
for
A320 family
WG used around 3100
photos of zones
3 aircraft other inspected prior to WG
(NWA msn 48, GFA msn 466 and CCM msn 548)
A320 EZAP Implementation
Number of tasks (For the A320 Family)
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 16
Interval (Months)
GVI DET RST Total
24 1 5 - 6
48 6 - 1 7
72 10 6 13 29
144 19 - 17 36
Total 36 11 31 78
A320 EZAP Implementation
A320 Zone 211/212
Area behind circuit breaker panel 121VU
(behind co-pilot)
Continuous air flow leads to dust accumulation
Cleaning recommended every 72 months
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 17
A320 EZAP Implementation
A320 Zone 127/128 - Feeder cables in avionics bay Existing Zonal Inspection every 48 months. Access to these cables requires galley / lavatory removal which is normally scheduled every 72 months.
Level upgraded to DET to avoid heavy access requirement at 48 months
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 18
A320 EZAP Implementation
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 19
Minimisation of maintenance burden
Maximum credit taken for existing Zonal Inspection Program to avoid dedicated tasks
Task intervals selected to coincide with Zonal Inspections
With few exceptions, new tasks will fit escalated 4C and 8C checks
No requirement to remove furnishings, galleys or lavatories earlier than already recommended
Need for cleaning tasks identified from examination of aircraft having at least 10 yrs in service
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 20
EZAP Output
The output of the EZAP is used to determine all the EWIS related ICA.
These tasks are implemented under the MRB process.
A compliance source document is delivered to the authorities listing sumarising EWIS related ICA in the various Airbus documents (MRBR, AMM, etc).
23-24 September 2014 Technology Evolution - Impact on Airtworthiness, Windhoek, Namibia 21
SIASA project
This project is funded by the European Union and implemented by EASA.
End slide
© AIRBUS S.A.S. [2014] All rights reserved. Confidential and proprietary document. This document and all information contained herein is the sole property of AIRBUS S.A.S. No intellectual property rights are granted by the delivery of this document or the disclosure of its content. This document shall not be reproduced or disclosed to a third party without the express written consent of AIRBUS S.A.S. This document and its content shall not be used for any purpose other than that for which it is supplied. The statements made herein do not constitute an offer. They are based on the mentioned assumptions and are expressed in good faith. Where the supporting grounds for these statements are not shown, AIRBUS S.A.S. will be pleased to explain the basis thereof. AIRBUS, its logo, A300, A310, A318, A319, A320, A321, A330, A340, A350, A380, A400M, ACJ are registered trademarks.