e zonal&l hirf principles

8/13/2019 E Zonal&L HIRF Principles

1/66

5 - 1XM33 Training MARCH 07

Maintainability & Maintenance Engineering + Maintenance Planning & Services

XM33 TrainingXM33 Training

5..Zonal L/HIRF logiconal L/HIRF logic

Principlesrinciplesbased on Airbus experience


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eserved.Confidentialandproprietarydocument.

XM33 Training - Zonal & L/HIRF Logic - Principles MARCH 07

THIS PAGE INTENTIONALLY LEFT BLANK


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Confidentialandproprietarydocument.


Zonal & L/HIRF logic - Principles

1. Introduction 4

2. Zonal & L/HIRF Analysis 9

3. MWG Review Process 61

4. Summary 64

Table of Contents


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1. Introduction MSG-3 Background


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Zonal inspections may be developed from application of the

Zonal Analysis Procedure. This requires a summary review of

each zone on the aircraft and normally occurs as the MSG-3

analyses of structures, systems,and powerplants are being

concluded. These inspections may subsequently be included in

the Zonal Inspections.

In top down analyses conducted under MSG-3, many support

items such as plumbing, ducting, Other Structure,wiring, etc.,

may be evaluated for possible contribution to functional failure.

In cases where a general visual inspection is required to assess

degradation, the zonal inspection is an appropriate method.


Zonal Analysis Procedure


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Changes of MSG-3 methodology since revision 2

New sections on:

Enhanced zonal analysis

L/HIRF analysis

Revised sections on:

Enhanced zonal analysis

ATA MSG-3

Operator/Manufacturer

Scheduled

Maintenance

Development

Revision 2005.1

ATA MSG-3


Scheduled

Maintenance

Development

Revision 2003.1

ATA MSG-3


Scheduled

Maintenance

Development

Revision 2002.1

ATA MSG-3


Scheduled

Maintenance

Development

Revision 2001.1

ATA MSG-3


Scheduled

Maintenance

Development

Revision 2

Changes of MSG-3 methodology since revision 2

Enhanced Zonal Analysis :

Allows appropriate attention to be given to safety related deterioration of wiring, particularly in zoneswith potential for combustible material accumulation

The main intent is to reduce existence of electrical ignition sources and combustible material throughmaintenance tasks

Changes in maintenance regulations have been addressed through an Aging Transport Systems

Rulemaking Advisory Committee (ATSRAC)

The Enhanced Zonal Analysis Procedure (EZAP) was developed by the ATSRAC Task 3 Sub-Committee

L/HIRF Analysis :

The intend of the L/HIRF protection tasks is to reduce the possibility that a single failure cause (e.g.lightning strike) and the occurrence of a common failure cause such as Environmental or Accidental

Damage (ED/AD) across (functional) redundant channels could impact aircraft airworthiness


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1. Introduction 4


2.1 Generic Process

2.2 Standard zonal Analysis

2.3 Enhanced zonal analysis

2.4 L/HIRF zonal analysis

2.5 Consolidation/transfer/interface


2. Summary 64

Table of Contents


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2.1 Zonal & L/HIRF Analysis - Generic Process

Zonal & L/HIRF general principles

MSG-3 document treats Zonal & L/HIRF in two independent sections

Zonal and L/HIRF analyses are performed as one unique proceduretaking advantage of the similarity between both processes

Zones are sensitive or not sensitive to L/HIRF threats. As per MSG-3,most of the L/HIRF protection and in particular the aircraft structurecontinuity are covered by the Standard Zonal Analysis

The Zonal L/HIRF analysis consists of the following sub-processes: Zone description

Zonal Analysis:

- Standard Zonal Analysis part (applies to all zones)

- Enhanced Zonal Analysis part (applies to zones with wiring)

Lightning/High Intensity Radiated Field (L/HIRF) Zonal Analysis(applies to L/HIRF protection elements)

Consolidation


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Any Airbus aircraft is divided into 9 major zones as follows:

Major Zones (External)

100 Lower half of fuselage (below cabin floor), including radome to ramp

Major Sub-Zones (Internal)

Sub-divisions of major zones, e.g. 100 is divided into 110, 120, 130

Zones (Internal)

Sub-divisions of major sub-zones, e.g.120 is divided into121,122,123...

200 Upper half of fuselage (above cabin floor) to end of main deck cargo

compartment300 Stabilizers and fuselage rear section400 Power plant (including propeller)

500 LH wing

600 RH wing

700 Landing gear & landing gear doors800 Doors

900 Special use (e.g. external fuel pods)


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Aircraft zoning principles (A340 example)


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Aircraft access panel numbering principles (A340 example)


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Inspection to be carried out from within touching

distance, unless otherwise stated

General Visual Inspection

(GVI)

The Zonal Inspection Program has one

single level of inspection!

Zonal Inspection Program (ZIP) principles

A mirror may be necessaryto ensure visual accessto all exposed surfaces in the inspection area


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The Zonal Inspection Program provides the General Visual Inspection

(GVI) requirements for each aircraft zone to inspect system and

powerplant installations for security and general condition and structure

for general condition

The Zonal Inspection Program is based on dividing the aircraft into

zones. Each zone is usually defined by a clearly defined physical

boundary, e.g. rib, bulkhead, frames, etc

Each zone is to be inspected as far as visible with the relevant access

open/removed

The extent of the inspection is defined by the access e.g. identification of

access doors, positioning of flight control surfaces, removal of lining and

insulation, etc

Inspections are recommended to be accomplished at or before stated

intervals



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Each zone is analysed for type of damage/deterioration to

structure/systems located in the zone which may occur in-service

Zonal inspection tasks do notprovide a summary of all the individual

systems and structural items to be inspected in the affected zone

Therefore it is considered that a person performing inspections has an

adequate knowledge of overall aircraft construction and systems

Zones may need more than one inspection at different intervals due to

the depth at which the zone is to be examined requiring different levels

of accessibility

- e.g. The cargo compartment requires 3 ZIP inspections each

requiring a different level of access (1.5 MO - door, 5 YE specific

panels and 10YE all access open)



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L/HIRF


Common Analysis Process

L/HIRF and Zonal analysis (Standard, Enhanced) procedures have beencombined to make maximum use of similar procedural steps & synergies

between the three zonal analysis parts

StandardZonal

Enhanced Zonal


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These visual

inspection

requirements

are covered

under the

Zonal

Inspection

Program

(ZIP)

Standard Zonal analysis:

- GVI (General Visual Inspection) Enhanced Zonal analysis:

- Stand-alone GVI, a GVI which is not performed as partof a zonal inspection

- RST (Restoration), cleaning being the most probable

- DET (Detailed Inspection)

L/HIRF protection analysis:



- FNC (Functional Check), resistance measurement

Structure & System/Powerplant maintenancerequirements transferred for consolidation include:

- GVI (General Visual Inspection)

- VCK (Visual Checks), system/powerplant analysis only


Zonal Inspection Program task levels (ZIP)


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These non

ZIP tasks

will be listed

in the

systems &

powerplant

section(ATA

chapter 20)


Standard Zonal analysis:

- GVI (General Visual Inspection) Enhanced Zonal analysis:


- RST (Restoration), cleaning being the most probable


L/HIRF protection analysis:



- FNC (Functional Check), resistance measurement

Structure & System/Powerplant maintenancerequirements transferred for consolidation include:

- GVI (General Visual Inspection)

- VCK (Visual Checks), system/powerplant analysis only

Enhanced zonal & L/HIRF task levels (ATA20)


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1. Introduction 3


2.1 Generic Process

2.2 Standard zonal Analysis2.2 Standard zonal Analysis





2. Summary 63

Table of Contents


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Standard Zonal

Zonal Inspection Program (ZIP) General Visual

Inspections (GVI) to detect visual degradation of thewhole zone content (structure, equipment, wiring,

L/HIRF protection, bonding leads, grounding points...)



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2.3 Zonal & L/HIRF Analysis - Standard Part

The standard zonal analysis process is based on four parameters:

- Accidental damage- Environmental damage

- Density

- Importance

The final rating in the matrix box provides guidance for the inspection

intervals (zonal guidance interval)

Intervals are defined according to applicable in-service experience

Standard zonal analysis principals

It is expected that the area to be inspected is clean enough to minimise

the possibility that accumulated dirt or grease might hide unsatisfactory

conditions Any cleaning that is considered necessary should be performed before

the zonal inspection task

Access is defined according to zone layout/installation


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321Low

443High

IMPORTANCE

HighModerateLow

432Moderate

DENSITY

ED FACTOR

4

4

33

211

433

ADFACTOR

21

322

24-48MO48-72MO72-96MO96-144MO2

48-72MO72-96MO96-144MO>144MO1


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Others

Others

Chemical (toilet fluids,..)

Contamination

Humidity

Vibration

Temperature

ENVIRONMENTAL

DAMAGE

N/A=0, Low=1, Moderate=2, High=3

Passenger traffic

Maintenance

Weather effects

Foreign objects

Fluid spillage

Ground Handling

ACCIDENTAL

DAMAGE

Cargo Handling

Although rarely used, the working group is notlimited to the given entries and may decide to

add further items to the given list entries

The highest rating will be taken into

consideration for the overall AD/ED rating

Zone accidental & environmental rating

Environmental Damage (ED):

This rating is a measure of howmuch the zone is subject to

temperature, vibration,

atmospheric exposure, moisture,

contamination

Accidental Damage (AD):

Each given and additionally

identified potential accidentaldamage cause will be rated in

respect of the possibility of

accidental damage to systemsand structure in the zone


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321Low

443High

IMPORTANCE

HighModerateLow

432Moderate

DENSITY


Density of equipment

Zone density and importance rating

This rating is a measure of how closethe various systems components(including wiring) are packed in a zone

The density is assessed relative to thesize of the zone

It provides indications about:

- The inspectability of the systeminstallation and structure

- The risk of common cause hazard

resulting in deterioration of multipleadjacent items (fire, burst, moisture,

fluid spillage)

The density refers to the number of

components and complexity


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321Low

443High

IMPORTANCE

HighModerateLow

432Moderate

DENSITY


Low:

System items whose anomalous behaviour may cause or contribute to failure

of system function with no effect on aircraft operational capability & pilotworkload but maybe undesirable economic impact and/or comfort reduction

Structure whose failure or detachment will not compromise continued safeflight or landing but where the potentially large size of released elements

needs to be considered

High:

PPH: Safety is considered asadversely affected if the

failure consequences wouldprevent the aircraft continued

safe flight and landing and/ormight cause serious or fatal

injury to human occupants

Moderate: Anomalous system behaviour may cause/contribute to fai lureresulting in adverse effect on aircraft operating capability

(delays, cancellations, ground/flight interruptions)

Structure whose failure or detachment could compromisecontinued safe flight or landing

Fuel tanks by default to limit frequent access and sub-sequent system disturbance/FOD

Anomalous system behaviour may cause or contribute to failure resulting in adverse effect on safety

Structure element whose integrity is essential

Zones where particular risks could affect several system items (hydraulic accumulator burst, wheel/tyrefailure, engine rotor failure, human error)

Fuel tank adjacent zones where failure of components (pneumatic system and/or ducting) could cause

localised heating of tank surfaces & consequently increase potential for auto-ignition of fuel Fuel leakage zones where temperature as result of failure (e.g. e lectric motors/transformers overload) could

increase and with potential ignition sources (electrical arcs , friction sparks) present


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INTERVAL EVALUATION

Access:Description/Boundaries:

GVI

Level ApplicabilityIntervalDescriptionAccessTask No.

321Low

443High

IMPORTANCE

HighModerateLow

432Moderate

DENSITY

ED F ACTOR

4

4

3

3

211

433

AD

FACTOR

21

322

24-48MO48-72MO72-96MO96-144MO2

48-72MO72-96MO96-144MO>144MO1


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The Zonal Inspection Program has inspection parameters in terms of

letter check and calendar time, as follows:

A - Check and multiples up to 4A

C - Check and multiples up to 4C

6Y/5Y and 10Y/12Y

The lower thresholds/intervals are mainly driven by the likelihood of

accidental damage and systems reliability aspects. The access is usually

limited to specific areas.

The higher intervals usually have a more significant access

requirement and are mainly concerned with the type of damage which

has propagated over time or cycles to the point where it is large enoughto be detected by a GVI.

7 Zonal Inspection Program2.3 Zonal & L/HIRF Analysis - Standard Part


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Standard zonal analysis summary

The Standard Zonal Analysis Part considers:

Overall rating results ina task interval guidance

Deterioration (e.g. corrosion, accidental damage, wear, ageing,fatigue) on systems components & airframe structures

Any deterioration of bonding & shielding of structure & equipment

(including wiring & L/HIRF protection) detectable by GVI

Evaluation is performed for

entire zone

any additionally dedicated access/area(s) of the zone can be

identified where appropriate

Using rating tables for:

Density

Importance Accidental Damage

Environmental Damage


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1. Introduction 3


2.1 Generic Process


2.3 Enhanced zonal analysis2.3 Enhanced zonal analysis




2. Summary 63

Table of Contents


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2.4 Zonal & L/HIRF Analysis - Enhanced Part

The Enhanced Zonal Analysis Procedure (EZAP) permits appropriate

attention to be given to electrical wiring installation within a zone(particularly in zones having the potential for combustible material

being present)

The logic provides a means to identify applicable and effective tasks tominimise combustible material accumulation and to address significant

wiring discrepancies that may not be reliably detected through Zonal

Inspection Program (ZIP) tasks

The enhanced zonal analysis must be performed for all zones thatcontain wiring

Enhanced zonal analysis principals


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Answers and explanations toquestions:

Justification for Interval:

Fuel leakage

Fuel vapour

Lint

Dust

CommentsY/NMaterial

Hydraulic mist

Oil mist

Level ApplicabilityIntervalDescriptionAccessTask No.

List if others..

Combustible material table

Description/Illustration:


Continue with EnhancedZonal Analysis Evaluation

Sheet 2

Standard Zonal Analysis isadequate. Continue with Task

Summary & Consolidation Sheet

Continue with L/HIRFZonal Analysis

Evaluation Sheet

NO

YES

Define task & interval

Is wiringclose to both

primary & back-uphydraulic, mechanical,

or electricalflight

controls?

combustible

material in thezone ?

Describe combustible material in table

Zone

contains wiring

?

Is therean effective task

to significantly reduce thelikelihood of accumulation of

combustiblematerials

?

NO

NO

YES

YES

YES

NO

NO

YES

Describe combustible material in table

L/HIRFprotection elements

installed in thezone?


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Tasks that avoidaccumulation of

combustibles(mostly cleaning)

Wiring inspectability

EE Bay?

Feeder (Route G)?

Flight compartment?

Wiring close to bothprimary and back-up

hydraulic, or electrical

flight controls?

Wiring

Combustible material

dust, lint, fuel vapours, fuel leakage, insulation

blanket (contaminated), oil mist, hydraulic mist


Dedicated WiringInspection

Enhanced zonal analysis principals


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Contamination with combustible material

Equipment and wiring are subject to dust and lint accumulation due to:

Air movement (natural, forced; typical areas are recirculation, galley & toilet etc.) Attraction by magnetic fields from electric current surrounding wiring and equipment

Combustible material impact:


Moisture trapping and subsequent corrosion

Changes in electrical characteristics (dust &

lint can act as conductor, e.g. with presence of

moisture, they can provide a path for a short

circuit)

Heat insulation which can cause overheat andpremature failure or contribute to fire ignition

Fire propagation in case of severe dust andlint accumulation

Wiring cleaning task are selected based on manufacturer/operators experience

Airbus has service condition experience from enhanced zonal exercises for legacy (Wide Body, Single Aisle,Long Range)


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It is considered useful to know the standard zonal GVI interval in order

to harmonise the overall access requirements

The assessment of DENSITY, SIZEand POTENTIAL EFFECT OF FIRE

IN ZONEprovides guidance on whether the zonal inspection program

GVI is adequate for all wiring in the zone, or if these GVI task(s) must be

augmented with stand-alone GVI(s) or DET inspection(s)

Most of the wiring is considered adequately addressed with the Zonal

Inspection Program (ZIP) GVI tasks

Some portion of wiring in the zone/area may require a dedicated

maintenance task (e.g. stand-alone GVI or DET) in respect to potential

fire ignition and/or potential for loss of multiple functions to the extend

that continued safe operation may not be possible

Dedicated wiring inspection task principles


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Size Comments:

Density Comments:

Potential Effect C omments:

INSPECTION LEVEL DEFINITIONZone Title:

Zone(s):

XXX/YYY/ZZZEnhanced Zonal Analysis Evaluation Sheet 2

Wiring inspection task level definition


3

3

2

High

11Small

33Large

SIZE

ModerateLow

21Medium

DENSITYENTIRE ZONE

EZAEZAEZAHigh

EZAEZAZIPModerate

ZIPZIPZIPLowPOTENTIALEFFECT OF FIREON ADJACENTWIRING AND

SYSTEMS IN THEZONE

SIZE / DENSITYFACTOR

321

Continue with Enhanced Zonal

Anal ysis Evalua tion Sheet 3

Continue with L/HIRF Zonal Anal ysis

Evaluation Sheet 1, i f protection installed

YESNO ZIP

adequate?

GVI

Dedicated

access

ZIP GVI for

the wholezone

Enhanced Zonal Analysis Evaluation Sheet 3(Stand-alone GVI or DET) for dedicated area

The need for a specific inspectiontask (Stand-alone GVI or DET) is

influenced by:

Size of the zone/area

Density of wiring/equipment

Potential effect of fire in the zone

Specific wiring installationwithin the zone

GVI or

DET

GVI or

DET


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Justification for Interval outside the guidance:

AreaComm ents/Illustration:

Potential Effect Comments:

Density Comments:

Size Comments:

LevelDescription ApplicabilityIntervalAccessTask No.

Zone Title:

Zone(s):

XXX/YYY/ZZZEnhanced Zonal Analysis Evaluation Sheet 3

Dedicated wir ing inspection taskExample


ENVIROMENTAL FACTOR

72MO1

24-12MO48-24MO3

ACCIDENTAL

FACTOR

21

48-24MO72-48MO2

SIZE / DENSITY FACTOR

POTENTIA L

EFFECT OF

FIRE ON

ADJACENT

WIRING AND

SYSTEMS IN

THE AREA DETDET

Stand

alone GVI

Stand

alone GVI

3

Stand

alone GVI

Stand

alone GVIStand

alone

GVI

High

21

Stand

alone

GVI

Moderate

Select the highest rating !

Others

Others

Chemical (toilet f luids,..)

Contamination

Humidity

Vibration

Temperature

ENVIRONMENTAL

DAMAGE


Passenger t raffic

Maintenance

Weather effects

Foreign objects

Fluid spillage

Ground Handling

ACCIDENTAL

DAMAGE

Cargo Handling

3

3

2

High

11Small

33Large

SIZE

ModerateLow

21Medium

DENSITYDEDICATED AREA

Continue with an additional Enhanced

Zonal Analysis Evaluation Sheet 3

Continue with L/HIRF Zonal Anal ysis

Evaluation Sheet 1, i f protection installedIs there an additional specific

access/area to be analysed?

NOYES

of boundaries and content of

dedicated area


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Comments on stand-alone GVIsZIP GVI Tasks:Zonal Inspection Programme GVI does not focus on particular

item or feature (the GVI task defined by the zone reference,access requirements and interval)

ATA20 GVI Tasks:

The term stand-alone GVI is used to identify GVI tasks

covering items or features that require particular attention in the

frame of the EZAP and/or L/HIRF analysis

All system (including wiring) and structure features evident with

the quoted access are subject to the inspection

Consequently stand-alone GVI are the same inspection level as any other ZIP,SSI or MSI GVI task

The difference to ZIP GVI tasks is that stand-alone GVIs focus on dedicated

items/issues whereas ZIP GVIs cover all items visible with the given access

Stand alone GVI tasks are listed in ATA chapter 20 (System &

Powerplant Section of Maintenance Program)

Stand alone GVI tasks focus on items clearly defined by the

task description (e.g. General Visual Inspection of P WiringRoute installed in the Main Deck Forward Cabin Overhead Area,

LH/RH)


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Enhanced zonal analysis summary

The Enhanced Zonal Analysis consists of two main parts:

Together from the assessment for the inspectabilitycriteria of a zone /dedicated area

1. Evaluation of combustible materialand possible reduction of arcingrelated risk All combustible material in the zone is listed

The related Description, Answers, Remarks, Comments and Justification

sections provide clear detail on the assessment

2. The wiringinspection level is evaluated using rating tables for:

Density

Size

Potential effect of fire on adjacent wiring and systems in the zone

As result, the analysis identifies if the ZIP GVI is sufficient for the whole

zone plus additional dedicated tasks (GVI-stand alone and/or DET) where

applicable

Note: The actual task interval is based on environment & accidental

damage assessment (as for the ZIP GVIs)


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1. Introduction 3


2.1 Generic Process



2.4 L/HIRF zonal analysis2.4 L/HIRF zonal analysis



2. Summary 63

Table of Contents


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G Route

(feeders)

P Route

Crossover

M & SRoutes to

Engine

L/HIRF

To detect L/HIRF protection degradation



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Lightning (L)

High Intensity Radiated Fields

(HIRF)

Radars

(ground &

airborne)

Radio

transmitters

2.5 Zonal & L/HIRF Analysis - L/HIRF Part

L/HIRF zonal analysis principals

The intend of the L/HIRFprotection tasks is to reduce the

possibility that a single failurecause (e.g. lightning strike) andthe occurrence of a common

failure cause such asEnvironmental or AccidentalDamage (ED/AD) across(functional) redundant channelscould impact aircraftairworthiness


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L/HIRF protection principalsEquipment protection

In addition to the equipment inherent protection (circuit layout and box design),clamping, filtering and transient protection devices (tranzorbs) prevent damagefrom induced voltage/current resulting from L/HIRF encounter

Hidden failure of these features is unlikely due to:

- High reliability figures of the transient suppressor

- Methodical shop testing after each unscheduled removal

- Build In Test Equipment (BITE)

System architecture

Is designed to achieve systems safety and availability objectives and contributesto increase the non-susceptibility of systems to L/HIRF effects

Main features are:

- Segregation of electrical wiring routes and equipment installation

- Redundancy and dissimilarity.

- Systems and functions monitoring (comparison, data coherence)


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L/HIRF protection principals

Aircraft structure continuity

Is ensured by metal to metal contact, bonding leads and meshes for compositestructure

Degradation (corrosion, broken strands) is covered by the standard zonal

analysis

Braided conduits and race ways (wings)

Provide wiring protection in exposed areas

Degradation is partially addressed with the standard zonal analysis and with

dedicated GVI and DET wiring inspection tasks defined through the enhancedzonal

The zonal L/HIRF protection analysis procedure will allow identification ofinspection tasks to augment these inspections


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Equipment protection:

Boxes designed with good EM

attenuation

Inputs and outputs fitted with

filters and transient

suppression devices

Electrical wiring protection:

Overbraiding/raceways in exposed

areas (wings, engines, landing

gear, belly fairing, )

Aircraft structure continuity:

Metal to metal contact

Metallic grid screen (mesh,

strip) on composite

Bonding leads

Systems architecture:

Segregation and routing of

electrical wiring routes

Different location of equipments

Redundancy and dissimilarity

System &powerplant analysis

Standard zonal,enhanced zonal &

L/HIRF analysis

Standard zonal &L/HIRF analysis Standard zonal analysis


Structure &standard zonal

analysis

L/HIRF protection principals


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MSG-3 zonal L/HIRF protection analysis scope


Electrical wiring protection:

Overbraiding/raceways in exposed

areas (wings, engines, landing

gear, belly fairing)

Exposed areas:

Open areas (landing gear, wing trailing

edge, )

Under low conductive material (titanium,

stainless steel, composite)

Wiring installed in the following areas are

protected:

Wings

Engine

Horizontal/vertical tail plane

Nose and main landing gear legs and gearcompartment

Radome

Sponson

Fairings

Tail area


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INSPECTION LEVEL

Description/Illustration:

INSPECTION INTERV ALL/HIRF key c haracteristics:

Justification for Interv al:

LevelDescription ApplicabilityIntervalAccessTask No.

Zone Title:

Zone(s):

XXX/YYY/ZZZL/HIRF Zonal Analysis Evaluation Sheet

DET

FNC

DET

FNC

DET

FNC

High

DENSITY

Standalone GVI

Standalone GVI

High

ZIPZIPLow

L/HIRFPROTECTION

DETERIORATIONCRITERIA

ModerateLow

Standalone GVI

ZIP orStand

alone GVI


End of Zonal Analysis.

Continue with Task Summary

& Consolidation Sheet

ENVIRONMENTAL FACTOR

72MO1

24-12MO48-24MO3

ACCIDENTAL

DAMAGE FACTOR

21

48-24MO72-48MO2

Select the highest rating !

Others

Others

Chemical (toilet fl uids...)

Contamination

Humidity

Vibration

Temperature

ENVIRONMENTAL DAMAGE


Passenger t raffic

Maintenance

Weather effects

Foreign objects

Fluid spillage

Ground Handling

ACCIDENTAL DAMAGE

Cargo Handling

YES

NO

ZIPapplicable

?

Determine Inspection

Requirements for ED/AD

Continue with an additional L/HI RF Zonal Analysis

Evaluation Sheet for additional specific protection itemsNOYES Are addi tional prot ection

items to be inspected?End of L/HIRF Zonal Analysis. Continue with

Task Summary & Consolidation Sheet


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Type Certification

process

Requirements/

compliance

Assurance

plan(TBD)

L/HIRF Assurance Plan is usually

implemented under the responsibility of theCivil Type Certificate holder and serves twopurposes:

To confirm that the design of the L/HIRF

protection is adequate to maintain TypeCertification objectives throughout aircraft life,

and

To identify specific locations within theL/HIRF protection system where there may

be a need for scheduled maintenance in

order to address any systematic deterioration

that could eventually impact the Type

Certification protection level


Type certificate relationship

Continued

Airworthiness


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Zonal L/HIRF protection analysis summary

The L/HIRF zonal analysis consists of 2 main parts

1. Assessment of required inspection level:

Density and potential effect of L/HIRF protection deterioration define

required level (ZIP or dedicated ATA chapter 20 L/HIRF task)

2. Evaluation of specific L/HIRF protection element if required

The task interval is based on assessment of environment & accidentaldamage similar to the enhanced zonal analysis

Density and potential reduction of overall L/HIRF protection define

required level (GVI stand alone, DET or FNC for each additional specifictask)


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1. Introduction 3


2.1 Generic Process




2.5 Consolidation/transfer/interface2.5 Consolidation/transfer/interface


2. Summary 63

Table of Contents


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Failure modes not identified

through the SSI/MSI

analysis but naturally

inspected by the zonal

2.6 Zonal & L/HIRF Analysis - Consolidation

Failure modes identified

through the SSI/MSI

analysis but naturally

inspected by the zonal(e.g. corrosion, obvious

deterioration)

MSI/SSI tasks transferred

into the zonal program


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Zonal Analysis

AIRCRAFT STRUCTURE

To be

consideredby Zonal WG

Significant?

OTHER

STRUCTURE

SIGNIFICANT STRUCTURE

Definition of

SAFE LIFE

LIMITS

FATIGUE

DAMAGE

ANALYSIS

ACCIDENTAL DAMAGE

ANALYSIS

ED/CPCP

ANALYSIS

ACCIDENT

AL

DAMAGE

ANALYSIS

ED

(Aging)

ANALYSI

S

Metallic or

Non Metal lic?

SAFE

LIFE

STRUCTU

RE

DAMAGE

TOLER ANT

STRUCTURE

METALLIC STRUCTURE

NONMETALLICSTRUCTUR

E

Safe Life or

Damage

Tolerant?

Y


N

The Zonal Analysis covers the entire aircraft regardless of the SSI selection

Thus the complete aircraft structure is considered by the zonal analysis!!!

TRANSFER

SSIsSSI analysis


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The zonal inspection will detect obvious unsatisfactory

conditions/discrepancies (accidental damage,

environmental deterioration, fatigue damage, ageing,general condition of fasteners, ) in all visible structure

(primary, secondary, fairing, panels, doors, )



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Systems evaluations are based upon the functional failures and the failure causes

Function(Normal

characteristicactions of an item)

Functional Failure(How an item failed to

perform its function)

Causes(Why the functional

failure occurs)

Failure effects(What is the result of

the functional failure)

Pipework and wiring are part of system installation,

but the related failure causes are normally not

considered by system analysis

All tubing, wiring installed in a zone is subject to

the zonal analysis and the resulting ZIP GVI

together with all other system and structure

However, the systems working group may select

MSI tasks for specific wiring/tubing in particularcases

The cause show functionaldegradation characteristics:

Mechanical fault

Electrical fault

Failing in open or closed position

Open or short circuit

Jammed linkage

Contaminated orifice

Broken housing etc.


Basic systems & power plant principal


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The zonal inspection will detect obvious unsatisfactory

conditions/discrepancies (due to accidental damage,environmental deterioration, ageing, ...) for all visible

systemcomponents (wiring, tubing, actuators,

computers, sensors, )



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2.7 Zonal & L/HIRF Analysis - Transfer

Systems/powerplant and structure program GVI items may be

considered as being covered by the ZIP as long as the followingcriteria are met:

A list of all transferred MSI task(s) and SSI task(s) covered by the

Zonal Program is available for reference (e.g. MRBR appendix)

Therefore, a dedicated inspection is not required for these SSI task(s)

and MSI task(s) if the equivalent ZIP task is performed

The access requirements of the MSI/SSI are the same as or less

severe than the ZIP task in the same area

The ZIP task is performed as frequently or more frequently than

the thresholds/intervals of the relevant MSI / SSI

Transfer requirement acceptance criteria


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Table of Contents

1. Introduction 4


3.3. MWG Review ProcessMWG Review Process 6161

4. Summary 64


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5.2 Composition of the Maintenance Working Group

Chair Person

Is appointed by Airbus Is accepted bythe ISC

ISC Advisor

Represents the ISC in

the group

Is nominated to adviseon policy issues.

Customer

Representatives

Operators

Manufacturer

Representatives

Airframe manufacturer

Engine manufacturer Major suppliers

MWG members and advisorsshould possess an adequate

level of knowledge andexperience.

Airworthiness Authorities(MRB)

Represents the

authorities in the group Participates in an

advisorycapacity

ADVISORS MEMBERS


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Table of Contents

1. Introduction 4



4.4. SummarySummary 6464


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4. Summary

The Zonal Analysis is a integrated approach with:

Combined description section

Zonal analysis with standard and enhanced issues clearly identified in dedicatedsections (the standard section covering certain L/HIRF issues)

Integrated zonal L/HIRF analysis part

Final consolidation

The actual zonal analysis consists of 3 main parts:

1.Standard zonal analysis to develop the ZIP general visual inspections

2.Enhanced zonal analysis addressing potential fire risk of wiring and relatedaccumulation of combustible material concern for in service aircraft

3.Zonal L/HIRF analysis to develop related tasks in terms of susceptibility to

degradation (acc idental damage / environmental deterioration)

The consolidation will derive

Harmonised zonal analysis results for both, the ZIP and ATA-20 tasks

The Zonal Inspection Programme (ZIP) including the transfers from systems &

structure


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AIRBUS S.A.S. All rights reserved. Confidential and

proprietary document.

This document and all information contained herein is the sole

property of AIR BUS 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 consentof AIRBUS S.A.S. This document and its content shall not be

used for any purpose other t han that for which it is supplied.

The statements made herein do not constitut e an off er. They

are based on the mentioned assumptions and are expressed

in good faith. Where the supporting grounds f or 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, A400M are regist ered t rademarks.


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