FAST / NUMBER 212

A330/A340CARGO BAY CONDENSATION

AND SMOKE WARNINGSSolutions available

In the last issue of the FAST magazine thecarriage of perishables and livestock

was discussed. In this article a morespecific challenge to the cargo

smoke detection system,caused by excessive

humidity, is examined.

Pneumatic, Fire and Ice Protection Engineers,Engineering and Technical Support, Airbus Industrie, Customer Services Directorate

Claire Nurcombe

By

and Mike Carver

TheAirbus Air Cargo market forecast indi-cates that transportation

of cargo is the fastest growing area ofaviation, with the world’s freighterfleet growing at an annual average of6.7% until 2015. A large amount of thecargo carried will be moisture and heatcarrying, e.g., animals, fruit and veg-etables. This moisture and heat has thepotential to be released over the periodof time that the cargo remains in thehold. Operations in hot and humid en-vironmental conditions can also lead tooccurrences of the same phenomenon.With the opening of the cargo doorsthere is an influx of hot and humid air.This affects the environmental condi-tions within the hold in the same wayas the presence of heat and moistureproducing cargo. False smoke alarmsmay occur in both circumstances dueto interference of condensation withthe smoke detection system.

The condensation formation may beaffected by the ventilation and heatingoptions for the cargo hold taken by theoperator. There are several options forventilating and heating the cargo bays.In the forward cargo bay there is a ba-sic option for ventilation, and tempera-ture control and/or ground ventilationcan also be installed. In the aft com-partment ventilation is a basic optionand in the bulk cargo bay ventilation isfitted on all aircraft. In the bulk cargobay heating and/or ground ventilationcan also be installed.

The ventilation systems for the for-ward, aft and bulk cargo compartmentsall have the same architecture. Twofans are fitted, one to draw air into thecompartment and one to draw out air.The expelled air is ducted towards theoutflow valve, which ensures that mostof the air is not recirculated. Since thisis only operative in flight there is anextra option to enable ventilation onthe ground.

The option for heating the bulk cargobay consists of an heating elementheating the incoming air. There is notrue regulation of the system; it is onlypossible to heat the bulk cargo com-partment, and there is no facility forcooling the compartment. This systemdiffers from the forward cargo bay sys-tem, which allows true temperaturecontrol, with heating and cooling of thecompartment.

Both heating and ventilation shouldensure that in-flight spurious smokewarnings due to condensation are pre-vented (since the detectors will bewarmed by the heated circulating airand the ventilation will help reduce the

amount of water vapour in the air).However, in cases of the carriage ofextreme humidity producing cargo, in-flight spurious warnings due to con-densation may still occur. Also, withthe cargo hold at a nominal tempera-ture of 20°C, condensation formationis still possible if the cargo doors areopened in very hot and humid condi-tions, where 20°C may be below thedewpoint temperature of the outsideair.

Condensation forms because the de-tectors are cooler than the air enteringthe cargo hold, either because of venti-lation in the hold, or because of thecold soak during a long flight. Whenthe hot and humid air enters the cargobay a disparity occurs between the rel-ative humidity within the hold and thetemperature of the detectors. This maylead to the situation where the dew-point temperature of the humid air isabove the temperature of the detectors.In these conditions condensation canform on the grid in the measuringchamber of the smoke detector. Thecondensation causes a change in thecurrent in the measuring chamber,which is the criteria for giving a smokealarm. These false alarms occur onlong range aircraft of all types, this for-mation of condensation being exacer-bated by the length of time a long haulaircraft may be airborne.

Over the duration of the flight, if nocargo ventilation is present, the humid-ity level in the cargo bays will increasewhile the temperature of the smoke de-tectors drops. This provides the perfectconditions for condensation to form.

A solution has been developed byAirbus Industrie to prevent spuriousalarms due to condensation occurringon the A330 and A340 aircraft.

FAST / NUMBER 21 3

CARGO COMPARTMENT A330-300 A340-200MODIFICATION OPTIONS /A340-300

Forward Ventilation (basic option) Mod 40096 Mod 40186compartment Temperature control Mod 40097 Mod 40188

Ground ventilation Mod 40220 Mod 40220

Aft Ventilation (basic option) Mod 40098 Mod 40190compartment

Bulk Ventilationcargo Compartment heating Mod 40099compartment Ground ventilation Mod 40221

Cargo compartment smokedetector hood

Forwardcargo

compt.

Aftcargo

compt.

Smoke

Smoke

Avionics

Smoke

FAST / NUMBER 21

SYSTEM OPERATION

The lower deck cargo compartment(LDCC) smoke detectors on the A330sand A340s are installed in pairs. Eachpair of detectors is supplied withpower by a dual redundant power sup-ply (see Figure 1). One detector in thepair is installed on the SmokeDetection Control Unit (SDCU) loopA, the other on loop B. To trigger analarm a signal from each detector inthe pair is needed. However, if oneloop is not functioning, a signal fromonly one detector is able to trigger analarm. The SDCU tests each loop tocheck whether it is functioning beforeit acts on a smoke alarm from a singlesmoke detector. When a smoke alarmis generated by the SDCU the ventila-tion and heating systems (if installed)will be closed automatically.

The detectors used on Airbus aircraftare of the ionisation type that detectboth visible and invisible fire aerosols(particle diameter between 0.01m to10µm). The ionisation detector utilisesthe phenomenon that air ions are at-tracted by smoke particles. The elec-trodes set up an electric field and theair between the electrodes is ionised(made electrically conductive) by aweak radioactive source (refer toFigures 2 and 3 for schematic diagramsof the smoke detector operation).These ions move under the influenceof the electric field, setting up an ioniccurrent. Smoke particles are too large(up to 1000 times larger than the ions)to be ionised and also attract the ionspresent between the electrodes. Theseresulting heavy ions are virtually im-mobile, reducing the ionic current,which as a consequence increases theelectrical resistance of the measuringchamber. An imbalance is now presentbetween the measuring chamber and areference chamber. This imbalance involtage is amplified and compared tofour different threshold levels:● The smoke threshold. The voltage atwhich the detector recognises thatsmoke is present in the measuringchamber and gives an alarm signal.● The prefault high threshold. Thevoltage at which the detector senses arise above the normal operational volt-age range.● The prefault low threshold. The volt-age at which the detector senses a fallbelow the normal operational voltagerange.● The fault threshold. The voltage atwhich the detector gives a fault signal.

The reference chamber in the detec-tor is present to allow for differentialpressure and temperature changes en-suring that the detectors operate withthe same sensitivity in flight and on theground.

Battery BUS28VDC

Channel 1Loop A

Channel 1Loop B

Channel 2Loop B

Smoketest

LDCCsmoke lamps

Avionics compartmentsmoke lamp

Avionicscompt.smoke

detector

Lavatorysmoke

detectors

Lavatorysmoke

detectors

Crew restsmoke

detectioncontrol unit

Stairwellsmoke

detector

Avionicscompt.smoke

detector

LDCCsmoke

detectors1WH3WH5WH7WH9WH

LDCCsmoke

detectors2WH4WH6WH7WH

10WH

Powerchannel 1

Powerchannel 2

Normal BUS28VDC

SDCUSmoke

DetectionControl

Unit

4

Figure 1Smoke detection loop schematic for A340

INVESTIGATION

The investigations into the spurioussmoke alarms due to condensationwere mainly concentrated with two op-erators, one operating in the MiddleEast and one in the Far East.Questionnaires were also sent to otherA330/A340 operators susceptible tospurious warnings to discover howwidespread the spurious alarms were.Some common factors high-lighted inthe replies to the questionnaire allowedAirbus Industrie to suggest some shortterm solutions to help reduce delaysand inconvenience. An effective shortterm solution was drying the smokedetectors with a hot air source, but thiswas a maintenance burden and notpractical for the operators in the longterm. It was also suggested that thecabin should be heated to the maxi-mum temperature (28°C) if no passen-gers were present on the flight, to havethe cargo ventilation, if installed, on atall times and to heat the bulk cargohold, if possible.

In January 1995 testing took placeon an A340 to define the environmentand to determine the effect of localisedheaters on the smoke detectors. One ofeach pair of detectors was instru-mented to measure temperature, hu-midity, sensitivity and smoke indica-tion. The cabin temperature, aircraftskin temperature and the ambient con-ditions on the ground were alsorecorded for each flight.

In total five flights were made, thefirst between Hong Kong and Osakaand the other four between Singaporeand Hong Kong. The last two flightsmade were with heaters fitted in smokedetectors 1WH and 7WH (the two de-tectors seen as being most susceptibleto the formation of condensation, seeFigure 4 on the following page). Thissusceptibility to condensation when thecargo doors are opened was shown byinformation previously taken duringthe investigation. This susceptibility isprobably due to proximity to the door.

The conditions on the ground (tem-perature approximately 25°C, relativehumidity 50-100% throughout the testperiod) did not lead to any falsealarms, but enough data was collectedfrom flights 2 and 3 to be able to con-clude that there was a direct, althoughsmall, influence of hot and humid con-ditions on the smoke detector sensitiv-ity signal.

On flight 2 the sensitivity dropped.The signal moved from -4.6V to -4.9Von 1WH (the detector was not heatedon this flight, -4.5V being the normalsignal and -6.0V a smoke alarm), whileon flight 3 the sensitivity dropped, thesignal changing from -4.9V to -5.2Von 3WH (an unheated detector).

The lowest sensitivity signal wasshown after the cargo doors had beenshut. Installing a heater to the smokedetectors did not have any detrimentaleffect on the smoke detector sensitivitysignal.

FAST / NUMBER 21

Figure 3Cargo smoke detector - Description of operation during smoke conditions

Figure 2Simple schematic of cargo smoke detection operation

Electrode

Ionisationsources

IonsFire aerosols

During smoke conditions the ion flow in the measuring chamber is impededwith relation to the reference chamber. This creates an imbalance betweenthe two chambers and a smoke alarm is generated.

Reference chamber

Measuringchamber

Ionisation source

Reference chamber shell

Fire aerosolsIonisation source

5

Airbus currently uses the ionisation type of smoke detectors but is also undertaking a review into the latest technologyoptical smoke detectors. The Scattered Light Detector is the optical smoke detector which is most suited for the use incargo holds. The photodiodes used in these detectors are semiconductor devices for detecting and measuring radiantenergy (as light) by means of its conversion into an electric current. The photodiodes and LEDs are arranged so that light from the LEDs does not fall on the photodiodes under normalconditions. The optical properties of some types of fire aerosol lead to a scattering of the emitted light, some of which willfall on to the photodiodes. This increase in the amount of light detected by the photodiodes causes a change in the electric current output by thephotodiode.

FAST / NUMBER 216

EVALUATION

Following the results of the flight test-ing, it was decided to proceed with aheated smoke detector design, ratherthan a change to the grille design oradding a curtain to the cargo bay doors.

Heating the smoke detector raisesboth the temperature of the detector it-self and the air inside the detector.Both of these help to reduce the rela-tive humidity within the measuringchamber.

Heating the detector also raises thedetector temperature higher than thedewpoint temperature of the ambientground conditions (or the dewpoint ofthe cargo). These factors reduce thelikelihood of condensation forming. It

was decided that the optimum way ofheating the detector would be to heatthe cell cover inside the protectivecover, which would ensure a minimumtemperature differential between thereference and the measurement cham-bers. It was decided to regulate thetemperature of the smoke detector to15 degrees over the ambient conditions(to a maximum of 40°C) to optimisethe detection ability. Each pair of de-tectors has a dual redundant heaterpower loop and as before, the SDCUwould check and verify smoke alarmsfrom just one detector.

An Electromagnetic Inductance filterwas also required for the smoke detec-tor. Fluctuations in the 28V electricalbus can occur during switches between

Forwardcargocompartment

3WH4WH

FWD

1WH2WH

Aftcargocompartment

Bulkcargo

compartment

FWD

5WH6WH

7WH8WH

9WH10WH

AIRBUS INDUSTRIE IS CURRENTLY EXAMINING NEW ADVANCES IN OPTICAL SMOKE DETECTORTECHNOLOGY

Figure 4Position of smoke detectors within the cargo bays

power sources (ground power, APUand engines). These fluctuations couldcause the heater coil to act as a sole-noid, producing a magnetic effect thatcould either cause a loss of smoke indi-cation capability or false smokealarms. The electronic filter preventssuch adverse side effects.

The evaluation units were tested forsix months in operational conditions.At the end of the evaluation period itwas judged that the heater coil wassuccessful in preventing spurioussmoke alarms. During the six monthsno spurious warnings had occurred,against what could normally be ex-pected (between three or four spurioussmoke warnings per month to three orfour per week, depending on the opera-tor and the environmental conditions).

FAST / NUMBER 21 7

• Mod 43967 - Wiring• Mod 44177 - Heated smoke detectors Available through the A330/A340 LRIP (Long Range Improvement Programme)

• SB 26-3009 (A330) and SB 26-4011 (A340) - Wiring for heater and EMI filter boxIssue date: Rev. 2, 30.09.9

• SB 26-3014 (A330) and SB 26-4015 (A340) - Fitting of heated smoke detectorIssue date: 04.06.96

Two Service Information Letters have also been issued concerning false smoke alarms. These give advice about the environmental and operational conditions that could give rise to false warnings. • SIL 26-003 (A300)• SIL 26-022 (all aircraft types)

Heated smoke detector P/N 4370-264

THE SERVICE BULLETINS AND MODIFICATIONS THAT ARE AVAILABLE ARE SHOWN BELOW:

CONCLUSION

Retrofitting the modifications on in-service aircraft started at the beginning of 1996. The cargo smoke detectors are an essential component of the fire protection system, but are susceptible to false alarms if

the conditions in the hold are hot and humid. Long range aircraft of all types suffer from this phenomenon, but Airbus hassolved the occurrence of false alarms by introducing heated smoke detectors.

There were two main requirements for a new detector: ● The relative humidity within the smoke detector measuring chamber had to be reduced without compromising the detec-tors’ effectiveness. ● The dewpoint temperature of the detector had to be raised above the dewpoint temperature within the cargo bay.

Both of these requirements could be solved by heating the smoke detector to a nominal temperature above ambient condi-tions.

The new detector included a heater coil that was capable of causing electromagnetic interference. A filter was thereforeadded to the design to protect the detector from the effects of electromagnetic induction.

Six months of testing took place to ensure that the heated smoke detectors would enter service without the need for furthermodification.

The main uptake of the modification by operators has been in the Far and Middle East, since many European operatorshave not experienced problems with the cargo fire detection system. This is due to the less extreme environmental conditionsencountered in Europe and as the man-hours required for the wiring modification are fairly substantial it is not seen as eco-nomical to perform this modification.

Airbus has successfully solved the occurrence of spurious alarms due to condensation on its long range aircraft. There havebeen no reported smoke alarms due to condensation from operators who have the heated smoke detectors fitted to their A330and A340 aircraft. ■

FAST / NUMBER 218

by Frédérique RigalA330/A340 Maintenance Systems EngineerEngineering and Technical SupportAirbus IndustrieCustomer Services Directorate

The concept of on-boardcentralised maintenance was

developed with the A320. The aimwas to provide maintenance teams

with diagnosis of faults in plainEnglish, through a single locationin the cockpit, with homogeneous

access to the maintenanceinformation related to the various

electronic systems. As a highlyinteractive tool, the Centralised

Fault Display System (CFDS) hasevolved with in-service experience,

which has also benefited theA330/A340 Central Maintenance

System (CMS) (described in FAST 16, April 1994) in terms of

homogeneity of interfaces anddefinition of layout, reports

and messages.

CENTRALCENTRALMAINTENANCEMAINTENANCESYSTEMSYSTEMOPTIONOPTIONPPAACKCKAAGEGE

A330/A340

Simplifying maintenance

9

TheCMS in the A330/A340family is based on thesame core principles and

basic functions as in the A320 family :● fault monitoring and diagnosis is undertaken by the Built In TestEquipment (BITE) of each system;● a dedicated computer, CentralisedFault Display Interface Unit (CFDIU)on A320 and Central MaintenanceComputer (CMC) on A330/A340, con-centrates the messages sent by theBITEs, edits maintenance reports andprovides an interface to the operatorwith the maintenance part of the con-nected systems;● a Post Flight Report is generated aftereach flight; it lists the ECAM warningsand maintenance status triggered duringthe last flight, as well as the corre-sponding fault messages produced bythe BITEs;● test capabilities and access to addi-tional systems maintenance informationare provided through the SystemReport/Test function.

In addition to these basic functions,Airbus Industrie, in cooperation withthe A330/A340 operators, has devel-oped a batch of new features to enlargethe capabilities of the CentralMaintenance System - The A330/A340CMS Option Package (Figure 1). Thispackage can be divided into three cate-gories :● features improving the Trouble

Shooting process by providing addi-tional information such as flags and ad-visories on the Post Flight Report(PFR) and new means of transmission:information downloading on to a disk,and sending BITE reports following up-link requests from the ground;● the Servicing Report gathers a num-ber of parameters, such as oil/liquidlevels, status of filters, pressures, etc.,with the aim of reducing the servicingworkload;● the Configuration ManagementReports allow the airline to know whichpart numbers, serial numbers and data-bases are fitted on their aircraft; everyconfiguration change is also detected,memorised and transmitted in real time.

FLAGS AND ADVISORIESON THE PFR

A Post Flight Report (PFR) (Figure 2)basically contains ECAM Warningsand Maintenance Status in the “cockpiteffects” column; the associated faultmessages are displayed on the sameline, in the “faults” column.

When an event occurs in flight, it isreported by the crew in the log-book. Ifit corresponds to an ECAM Warning, itis easy for the maintenance personnel toretrieve it on the PFR. Then, the corre-lated message in the “faults” columnprecisely identifies the faulty LineReplaceable Unit (LRU).

MAINTENANCE MENU 1 / 2

< FL IGHT REPORT - - - - - - - - -

< FL IGHT REPORTS

< AV IONICS STATUS - - - - - - -

< SYSTEM REPORT/TEST

< SERVIC ING REPORT

PRINT * >

PR INT * >POST

DUMP: SEND:

PREVIO US

1L

2L

3L

4L

5L

6L

1R

2R

3R

4R

5R

6R

MAINTENANCE MENU 2 / 2

< CLASS 3 REPORT

< REPORTS PROGRAMMING

< DATA BASE MANAGEMENT

< AV IONICS CONFIGURAT ION REPORTS

1L

2L

3L

4L

5L

6L

1R

2R

3R

4R

5R

6R

FAST / NUMBER 21

NEW FEATURES

• Servicing Report:List of servicing parameters for 10 items (engines, IDG, APU, Landing gear...)

• Avionics Configuration Reports:List of P/N, S/N and DB/N of systems connected to the CMC

• Dump of CMS Reports on a disc through the MDDU• BITE reports transmission upon Uplink Request

MODIFIED FUNCTIONS

• Post/Current/Previous Flight Report: Flag and Advisories

• Reports Programming:SRR and Configuration Change Report automatic PRINT/SEND/DUMP programmation.

• Data-base management: two new data-basesCustomised thresholds/Comments for SRR,and diskettes configuration data-base

Figure 1Central Maintenance Computer optional functions

FAST / NUMBER 2110

If an event is not related to an ECAMWarning, the correlation between thelog-book and the fault message on thePost Flight Report is done with theUTC (GMT), the flight phase and theATA Chapter of the affected system.

The innovation of the CMS OptionPackage is the recording, in the PFR“cockpit effects” column, of the red

flags and the advisories displayed dur-ing the flight on the Primary FlightDisplays (PFD), Navigation Displays(ND) and System Displays (SD). The37 new “cockpit effects” increase thenumber of cases where a direct correla-tion between the PFR and the log-bookis possible, giving less room for inter-pretation and more room for efficiency.

30

VOR1

VOR1

TRO ADF215

390095/20

380 116.00

TROCRS 010°

M

NM

GS

. 3

27

24

TAS

30

VOR1

VOR1

ADF2

390095/20

380CRS XXX

GS

27

24

TAS

Lateral deviation bar with TO/FROM indications

VOR 1:PointerIdentDistance

Selected VOR:Frequency

Red flag

IdentCourse

VOR

Figure 2Post Flight Report associated with flag example on Captain’s Navigation Display

MAINTENANCEPOST FLIGHT REPORT

LEG 00

CMC1 PRINTING

PAGE 01/01DATE DEC11UTC 0104

Source BMC2IdentifiersZC EIVMU2

Source PHC1IdentifiersADR1

Source CMC1

Source VOR1

ATA 361143Class 1IntermittentTHRM (5HA2) /FAN AIR V(12HA2)

ATA 341116Class 1HardL STATIC PROBE1(8DA1)/PHC1 (6DA1)

ATA 451334Class 2HardCMC2 (1TM2)

ATA 345531Class 1HardVOR1 (1RS1)

UTCFLIGHT PHASE

1232

Engine Start02

1240

Climb05

1907

Cruise06

2137

Cruise06

A/C IDENT .F-A3X4SATE DEC11FLT NB AI1234FROM/TO LFBO/WMKKSTART/END 1231/0057

04 COCKPIT EFFECTS

ATA 3621

NOT DISPLAYEDAIR BLEED LO TEMP

ATA 3031

ANTI ICE L CAPT STAT HEAT

ATA 4513

MAINTENANCE STATUSCMC1

ATA 3455

FLAG ON CAPT NDVOR1

04 FAULTS

END OF REPORT

Normal display Abnormal display

DOWNLOADING FUNCTION

With the development of data process-ing applications on standard PersonalComputers (PC), the need for mainte-nance information exploitable on a PCis rising. This is the reason why CMCand BITE reports can now be directlytransferred to a diskette inserted in theMultipurpose Disk Drive Unit (MDDU)in the aircraft.

This diskette must contain a configu-ration file, prepared with the groundsoftware Maintenance Option Tool(MOT) (see Figure 3). Data can bemanually transferred using the DUMPline key from CMS menus on theMulti-purpose Control and Display

Unit (MCDU), or automatically down-loaded at the end of the flight (PostFlight Report, Servicing Report). Acommand file can also be prepared withMOT, in order to automatically transferselected reports, upon insertion of thediskette into the MDDU.

REQUESTS FOR BITEREPORTS FROM

A GROUND STATION

Quick access to maintenance informa-tion can be difficult, when the cockpitis crowded during turnarounds.Besides, trouble-shooting of an aircraftat an out-station sometimes requires thecompetence of main-base engineers,

Figure 3Preparation of the diskette

ADR1

< REPORT

< REPORT

< LRU IDENT

< GROUND SCANNING

< DATA

< RETURN

FAULTS >LA S T LE G CLA S S 3

TEST >S Y S TEM

TEST >RAT

TESTS >OUTP UT

REPOR T >GROUND

STAT US >CURRE NT

TROUB LE S HOOTING

P RE V IOUS LE GS

1L

2L

3L

4L

5L

6L

1R

2R

3R

4R

5R

6R

ADR1

UTC ATA1L

2L

3L

4L

5L

6L

1R

2R

3R

4R

5R

6R

Airline main base

ACARS

SMDADR1/1L,3

BITE report (*)

(*) Same formatas manual SEND

CMC

ADIRU1

LA S T LE G RE P ORT

ADM1 (19FP1 )0019 341117

ADIRU1 (1FP1 )0019 341234

< RETURN

SEND:

SEND*

DATA LOADER

Downloading on event/manual download:CONFIG.LDRMOTIDENT.330 or MOTIDENT.340.F-A3X4.PFR (Standard file name).F-A3X4.SRR etc...

Semi-automatic downloading:CONFIG.LDRMOTIDENT.330 or MOTIDENT.340CMC.DLFMANUAL.PFR (Operator file name)MANUAL.SRR etc...

MOTDISKETTE

EDIT

MOT

Master CMC

Compatible IBM PC

Compatible IBM PC

Figure 4CMC interrogation from main base

FAST / NUMBER 21 11

and would be much facilitated if theyhad the possibility of accessing themaintenance reports and system infor-mation in real time. This is the reasonwhy new uplink requests have been de-fined, which can specify the exactBITE report that is needed. These com-mands are sent by radio (ACARS) fromthe main-base ground station to theCentral Maintenance Computer; the lat-ter initiates a dialog with the requestedsystem, simulates the line keys in orderto give access to the specified report,and retransmits it via ACARS in thesame format as a usual SEND from thecockpit (see Figure 4).

As with direct access through the

MCDU System Report/Test, the BITEuplink requests are inhibited in flight,and the System Dual Access (i.e. con-flicts when a system is being accessedfrom several peripherals) is managedby the CMC. Of course, any commandcorresponding to system tests is auto-matically rejected by the CMC, in orderto ensure a totally safe use of this fea-ture.

SERVICING REPORT

The purpose of this MaintenanceServicing Report is to gather parame-ters from various systems involved inperiodic checks and which might lead

Figure 5Example of Servicing Report pages

A/C IDENT

DATE

FLT NB

FROM/TO

START/END

GATEOUT/GATEIN

TAKEOFF/LANDON

ENGINES

ATA 121379

ATA 121379

ATA 792110

ATA 731110

ATA 783000

ATA 792150

IDG

ATA 121324

ATA 121324

ATA 242100

APU

ATA 490000

ATA 121349

ATA 499111

HYDRAULIC POWER

ATA 121229

ATA 291400

OIL LEVEL

OIL CONSUMPTION

OIL FILTER STATUS

FUEL FILTER STATUS

REVERSERS INHIBITION

OIL CHIPS DETECTORS

OIL LEVEL STATUS

OIL FILTER STATUS

DISCONNECTION STATUS

OPERATING HOURS

APU OIL LEVEL STATUS

CHIPS DETECTION

LEVEL INDICATION

RESERVOIR PRESS STS

MAINTENANCE

SERVICING REPORT

ENGINE 1

18.8 QT

0.34 QT/HR

OK

CLOGGED

OK

OK

IDG 1

LOW LEVEL

OK

OK

160 HOURS

OK

OK

GREEN SYSTEM

REMOVE

OK

ENGINE 2

18.4 QT

0.34 QT/HR

OK

OK

INHIBITED

OK

IDG 2

OK

OK

OK

NUMBER OF START CYCLES 224

BLUE SYSTEM

ADD

OK

ENGINE 3

18.4 QT

0.46 QT/HR

OK

OK

OK

CHIPS DET

IDG 3OK

CLOGGED

OK

ENGINE 4

19.3 QT

0.39 QT/HR

CLOGGED

OK

OK

OK

IDG 4

OK

OK

DISCONNECTED

YELLOW SYSTEM

OK

OK

CONTINUED

CMC1 PRINTING

PAGE 01/02

DATE DEC11

UTC 0114

.F-A340

DEC11

AI1234

LFBO/WMKK

1231/0057

1225/0108

1238/0048

SERVICING REPORT CMC1 PRINTING DATE DEC11 UTC 0114 PAGE 02/02

FUEL

ATA 121100

LANDING GEAR

ATA 121432

OXYGEN

ATA 121435

DOORS

ATA 521000

AND

SLIDES

ATA 256241

WATER/WASTE

ATA 121529 WATER

ATA 122438 WASTE

AIR CONDITIONNING

ATA 215225/215226 EXCHANGER

TOTAL FUEL ON BOARD 41850 KG

14130 KG LH INNER TANKS RH 13890 KG

2800 KG OUTER TANKS 2900 KG

CENTER TANK 8050 KG

TRIM TANK 0 KG

CREW OXYGEN BOTTLE PRESSURE 1722 PSI

SUPPLEMENTARY CREW OXYGEN BOTTLE PRESSURE 1064 PSI

PAX OXYGEN BOTTLE PRESSURE 1874 PSI

BTL PRESS STS

FWD

MIDDLE

EMERGENCY

AFT

DOOR

1L OK

2L OK

3L OK

4L OK

DOOR

1R OK

2R OK

3R LOW PRESSURE

4R OK

SLIDE

OK

OK

OK

OK

SLIDE

OK

OK

OK

OK

POTABLE WATER

FORWARD TANK WATER LEVEL 95%

AFT TANK WATER LEVEL 100%

WASTE WATER NOT EMPTY

LEFT TANK LEVEL 20%

RIGHT TANK LEVEL 43%

HEAT EXCHANGER 1 OK

HEAT EXCHANGER 2 CONTAMINATED

END OF REPORT

TYRE PRESSURE(PSI) NOSE GEAR 160 - 165 160 - 165

BRAKE TEMP (DEGREE C) 1:25/215 2:30/175 3:10/205 4:10/185

/TYRE PRESSURE(PSI) 5:25/200 6:25/205 7:10/195 8:15/210

TYRE PRESSURE(PSI) CENTRAL GEAR 170 - 165

FAST / NUMBER 2112

to a servicing action. Once again, byconcentrating the information on a sin-gle report, the aim is to simplify main-tenance and to save time. This is partic-ularly valuable when the aircraft isoperated with short turn-arounds, andwhen specific regulations, such as forETOPS operations, require additionalchecks.

The Servicing Report (SRR) is avail-able on two formats:● the full mode SRR is a two page re-port (Figure 5), which lists all the fol-lowing parameters, should they requirea servicing action or not:● engines, ● IDG, ● APU, ● hydraulic, ● fuel, ● landing gear, ● oxygen, ● doors and slides bottles, ● water/waste,● air conditioning. The monitored parameters are: ● levels of oil, fuel, water, and hy-draulic fluid, ● status of filters, ● pressures of bottles, tires, reservoirs,

● chip detection, etc.● the coupon mode SRR presents onlythe systems which have at least one pa-rameter requiring a servicing action. Asummary is always issued first, in orderto indicate the status of each system:OK or CHECK. This summary is fol-lowed by a variable number of“coupons”, each of which gives the ser-vicing parameters of the systems de-clared “CHECK” in the summary (seeFigure 6).

It should be noted that every parame-ter is computed by the CMC with a par-ticular logic, in order to always displaythe more significant value; for example,fuel & water levels are real time infor-mation, whereas engines oil levels arenot shown in flight but presented in realtime during five minutes on the ground,and then memorised until the next start.This logic allows minimisation of theerrors introduced by the oil cooling andthe gulping effects.

The Servicing Report can beCustomised, using files prepared withthe MOT ground tool, and uploadedinto the CMC:● on every coupon, and after every itemof the full report, spare space is avail-

A/C IDENT

DATE

FLT NB

FROM/TO

START/END

GATEOUT/GATEIN

TAKEOFF/LANDON

ENGINES-OIL LVL FLTR CHIPS FUEL FLTR REV

IDG-OIL LVL STS FLTR DISC

APU-OIL LVL STS CHIPS

HYDRAULIC SYSTEMS-LVL RSVR AIR PRESS

FUEL TANKS-QTY

MAINTENANCE

SERVICING SUMMARY COUPON

DB/N AIB

END OF SERVICING REPORT SUMMARY COUPON

CMC1 PRINTING

PAGE 01/01

DATE DEC11

UTC 0114

.F-A330

DEC11

AI1234

LFBO/WMKK

1231/0057

1225/0108

1238/0048

CHECK

OK

OK

CHECK

OK

CHECK

OK

OK

CHECK

OK

LANDING GEAR-TEMP PRESS

OXYGEN BOTTLES-BTL PRESSURE

DOORS AND SLIDES BTL-PRESS STS

WATER/WASTE TANK-LVL

AIR CONDITIONING-EXCHANGER FLTR

A/C IDENT

DATE

FLT NB

FROM/TO

START/END

GATEOUT/GATEIN

TAKEOFF/LANDON

ENGINES

ATA 121379

ATA 792110

ATA 731110

ATA 783000

MAINTENANCE

SERVICING ENGINES COUPON

DB/N AIB

END OF ITEM COUPON

CMC1 PRINTING

PAGE 01/01

DATE DEC11

UTC 0114

.F-A330

DEC11

AI1234

LFBO/WMKK

1231/0057

1225/0108

1238/0048

OIL LEVEL

OIL FILTER STATUS

FUEL FILTER STATUS

REVERSERS INHIBITION

ENGINE 2

18.4 QT

OK

OK

INHIBITED

ENGINE 1

18.8 QT

OK

CLOGGED

OK

Figure 6Servicing Report - Coupons

FAST / NUMBER 21 13

able for the insertion of comments.These comments can be specific recom-mendations or information for the me-chanics;● the title of the complete servicing re-port and of the summary coupon can bemodified;● for every numerical parameter, maxi-mum and minimum thresholds can bedefined. If the actual value exceeds thisrange, the status of the system becomesCHECK, and a coupon will be trig-gered if the coupon mode is selected.

The Servicing Report can also be au-tomatically printed and/or sent throughACARS and/or dumped on a disc, 10minutes after engines shut-down, whichis the delay needed to get stabilised oillevels.

AIRCRAFTCONFIGURATION

REPORTS

The last feature of this option packageis the capability of managing aircraftconfigurations. For that purpose, threereports have been designed, theEquipment Configuration Report, theDiskette Configuration Report, and theConfiguration Change Report.● The Equipment Configuration Report

(ECR) gives in real time the completelist of part numbers (P/N), serial num-bers (S/N) and, when applicable, data-base numbers (DB/N) of equipmentconnected to the CMC (Figure 7). Thislist is accessible from the MCDU, it canbe printed, sent through ACARS, re-quested from ground with an uplink ordumped on a disk. It is automaticallyupdated when new equipment is fittedon the aircraft.● A Configuration Change Report(CCR) is created each time a part num-ber or data-base number change is de-tected by the CMC. It can be automati-cally printed/sent/dumped, allowing theresponsible ground staff to be aware inreal time of any configuration change.For each modified equipment, the CCRremains accessible from the MCDU, aslong as the change has not been vali-dated through a specific menu with apassword.● The Diskette Configuration Report(DCR) is a list of the disks associatedwith the avionics; for each of them, thereport provides the reference of the datathey contain (Navigation data-bases,software loaded by disk, filter data-bases, etc.). The frame of this report isdefined with the Maintenance OptionTool (MOT) ground software.

CONCLUSION

The new features developed in the option package of the A330/A340 Central Maintenance System, recording of red flags onPost Flight Reports, transfer of on-board data to diskettes, direct access from ground station to on-board data, and aircraft con-figuration reports, enlarge the capabilities of this trouble-shooting tool, which also becomes a servicing and a configurationmanagement tool. Maintenance is simplified and time is saved.

This new step in modern maintenance confirms Airbus Industrie’s desire to develop powerful and efficient tools, which takefull benefit from digital technology and adapt maintenance practices to the latest generation of aircraft. ■

FAST / NUMBER 2114

Figure 7Equipment Configuration Report

MAINTENANCEEQUIPMENT CONFIGURATION REPORT PAGE 01/06

AIRCRAFT IDENTIFICATION .F-A330 PRINTING DATE DEC11 UTC 0117

ATA 212634

ATA 212834

ATA 213134

ATA 213134

ATA 201124

ATA 201124

NAME AEVCSYSTEM AEVC

NAME VCSYSTEM VC

NAME CPC 1SYSTEM CPC1

NAME CPC 2SYSTEM CPC2

NAME ZCSYSTEM ECS

NAME PC1SYSTEM ECS

P/N: 785-611-2S/N: 0231

P/N: 600623-70-602S/N: 20200

P/N: 7125-19900-01AAS/N: 9512507

P/N: 7125-19900-01AAS/N: 9512506

P/N: 978B0000-01S/N: 00055

P/N: 977A0000-05S/N: 00390

The A330/A340 CMS option package is available through the RFC/RMO procedure. For more technical information, do not hesitate to contact AIRBUS INDUSTRIE, Customer Services, AI/SE-E54 Tel: +33 (0)5 61 93 29 42, or your Customer Support Manager. The modification is covered by SB 45-3005 and 45-4005.

FAST / NUMBER 21 15

GGEETTTTIINNGG HHAANNDDSS--OONN EEXXPPEERRIIEENNCCEE

WWIITTHH AAEERROODDYYNNAAMMIICCDDEETTEERRIIOORRAATTIIOONN

This article is an extract of a brochure of the samename which covers the complete Airbus aircraft

family.

Today’s tough competitive environment forcesairlines to reduce their operational costs in every

facet of their business. Every method to achievethis goal has to be envisaged, safety and accident

prevention permitting of course, as these areprime factors in any aircraft operation. A wide

variety of different aspects have to be taken intoaccount in this process, such as Air Traffic

Control, engine deterioration, flight operationsmanagement, instrument accuracy or aero-

dynamic deterioration.

The purpose of this document is to examine the influence of aerodynamic de-

terioration.

by Jean-Jacques Speyer Manager Operational Evaluation Flight Operations Support Airbus Industrie Customer Services Directorate

FAST / NUMBER 2116

Themanufacturer does itsbest from the develop-ment phase onwards

to foresee all potential deteriorationsand adopt designs which are the leastsensitive to in-service deterioration andby continuous research and modifica-tion programmes, to keep the aircraftdeterioration processes within accept-able bounds. The operator’s responsi-bility is to maintain his aircraft in goodcondition and make sure that it isutilised in the most satisfactory condi-tions possible.

Unfortunately, in the life of an air-craft , degradation is likely to occur.An aircraft is normally expected to in-crease its drag by up to 2% within fiveyears if not properly maintained.Indeed, many aerodynamic elementsmay increase drag and their cumulativeeffect can introduce a significant costincrease. Simply adopting correctiveaction in order to repair these items,could lead to excessive maintenancecosts. Therefore, the effect of deterio-ration has to be traded-off against theestimated maintenance cost, in order tocheck whether it is cost-effective tocarry out corrective measures. Cost-benefit analysis is the only practicalway of keeping an aircraft opera-tionally efficient.

Airbus Industrie has carried out nu-merous performance audits in co-oper-ation with airlines which, implicitly,have made a very useful contributionto this document.

The information in this documentwill help the aircraft operator adapt itsmaintenance programme, balancing fi-nancial aspects, such as increased fuelconsumption against maintenancecosts. It should enable operators to de-termine whether corrective actions arefinancially pertinent, despite short-termmaintenance costs. Considerable

longer-term expense may thus beavoided at relatively low cost. Andstrategic maintenance actions ratherthan detailed, dispersed and costly re-pair jobs may be more easily decidedupon and justified.

GENERAL

Aerodynamic deterioration

Some of the most severe penalties interms of fuel consumption are causedby increased drag resulting from poorairframe condition. Normal aerody-namic deterioration of an aircraft overa period of time can include the incom-plete retraction of moving surfaces,damaged seals on control surfaces, skinroughness and deformation due to birdstrikes or damage caused by groundvehicles, chipped paint, mismatchingdoors and excessive gaps. All theseitems are potential money wasters.Each deterioration incurs drag in-crease, and this increased drag is ac-companied by increased fuel consump-tion.

Sensitivity classification

The fuel burn penalty caused by drag-inducing items is largely dependentupon the location and extent of theproblem; different areas of the airframeare more or are less sensitive to alter-ations in their optimum aerodynamicsmoothness. Bearing this in mind, azonal classification can be establishedfor drag sensitivity over the whole air-craft (see Figure 1).

Zone 1 surfaces require high aerody-namic smoothness because they are en-dowed with high local flow velocitiesand very thin boundary layers whichare very sensitive to small local distur-bance. Zone 3 surfaces are much lesssensitive because of lower flow veloci-

FAST / NUMBER 21 17

ties and thicker boundary layers, anddisturbance on these parts of the air-frame does not produce high aerody-namic resistance to the airflow. Also,the transition from laminar to turbulentboundary layers having occurred ear-lier, zone 3 is less sensitive to aerody-namic irregularities or excrescences.Finally, zone 2 surfaces represent anaverage between these two extremes.

The localisation of zones 1, 2 and 3for A300/A310 are shown in thefigure 1. The zones differ slightly forthe other Airbus aircraft.

Fuel penalty calculation

It is possible to determine drag in-crease, generated by particular items,with wind-tunnel measurements or an-alytical techniques. The drag increaseis then converted into terms of in-creased fuel burn - in US gallons peryear per aircraft - but the reader mustkeep in mind that the values given cor-respond to an aircraft which is in ac-cordance with specific assumptions.These assumptions refer to each typeof aircraft of the three Airbus families

Figure 1Drag sensitivity zones (A300/A310)

Zone 1 High sensitivity

Zone 2 Medium sensitivity

Zone 3 Low sensitivity

Aircraft upper surface

Aircraft lower surface

Front spar

Rear spar

Rear spar

Rear spar

FAST / NUMBER 2118

and include annual flight hours basedon airline statistics.

The drag increase can also be ex-pressed in US$ per year per aircraft,the fuel price being based at US$0.60per gallon. Note: fuel prices have in-

creased by about 30% in the last year.Since calculation assumptions mayvary significantly among individualoperators, tables giving a correctivefactor - to apply to the fuel penalty tobe derived from the operator’s annualflight hours - is given for each type ofaircraft, in Figure 2.

Airframe maintenance

For a specific corrective task, man-hours required can significantly varyfrom one airline to another, and fromone type of repair to another. The cal-culation method adopted in this docu-ment is simply an estimation partlybased on measurements. These tasksshould have been carried out assuminga regularly maintained aircraft, oper-ated under normal conditions and withan average daily utilisation, havingmaintenance /corrective actions carriedout in a hangar with good environmen-tal conditions. All necessary standardand special tools, as well as groundsupport equipment, skilled mainte-nance personnel and appropriate main-tenance documentation should also beavailable.

The values presented herein (menand manhours) are based on these as-sumptions and are intended to reflectoperational reality as closely as possible.

Total maintenance costs, for both on-

aircraft and shop tasks, include over-head and burden costs for maintenanceplanning, engineering orders, safetyequipment, facilities and supervision.An acceptable rate per manhour cover-ing all these aspects is US$50. Serving

as a benchmark, this value correspondsto an average cost covering skilledworking personnel.

Adapted maintenanceprogramme

As stated above, the degradations thatare likely to occur stem from two mainsources (excluding incidents or han-dling) : either mechanical wear or cor-rective actions which have not beenproperly executed. Although ill-consid-ered or superficial repair may havenegligible effect on performance, sometasks have to be carried out with spe-cial care, given their positive impact onfuel consumption.

As mentioned before, despite the ef-forts of maintenance organisations andmanufacturers, deterioration can occur.It may have significant effects on con-sumption in spite of having only aslight influence on drag. One way todetermine these effects is to use theAircraft Performance Monitoring(APM) software. This programme cal-culates deviations in Specific Rangeand, to some extent, helps to determinehow much these discrepancies stemfrom engine degradation and howmuch from a lack of aerodynamiccleanliness. Inherently, the programdoes not really differentiate betweenapparent and real drag.

Drag correctivefactor

Annual aircraft utilisation (hours)

2.0

1.5

1.0

0.5

02000 3000 4000

2.0

1.5

1.0

0.5

02000 3000 4000

2.0

1.5

1.0

0.5

02000 3000 4000 5000

1

1 A300

A300-600

A310

A319

A320

A330

A340

A321

2

3

1

2

3

1

2

11

22

3

23

Figure 2Corrective factor for drag penalty

FAST / NUMBER 21 19

For instance, higher drag may beconcluded from APM results butcould, in fact, reflect lower thrust at N1(or EPR). Also bleed leaks can affectapparent aerodynamic deteriorationthrough N1 deviations by biasing theN1/thrust relationship if they are notaccounted for. For these reasons, val-ues given by the APM software have tobe considered with great care.

Nevertheless, they can trigger analarm at a predetermined loss ofSpecific Range in relation to the initialaircraft drag condition, and an un-scheduled check could be launched todetect the type and location of any dragrise. This unscheduled check could bea line check walkaround associatedwith an overwing in-flight check ob-serving and photographing control sur-faces, preferably by means of a tele-photo or zoom lens. The association ofboth types of check constitutes anAerodynamic Inspection. The items tobe observed are shown in Figure 3.This Aerodynamic Inspection, whichwould take only a short time to per-form, should be done by skilled per-sonnel as for example aerodynamics orperformance engineers, able to inter-pret secondary effects (e.g. leakages)and to determine the corresponding de-viations (as well as being able to con-duct performance audits).

When both the type and extent of

the deterioration are known, the fol-lowing tables (example shown onFigure 4 on the following page)couldbe used to determine what should berepaired and what may be ignored, forfinancial reasons. Repair times shouldbe scheduled during night-time peri-ods, time permitting, otherwise the taskhas to be included in a scheduledcheck.

The Aircraft Performance Moni-toring software has the advantage ofpotentially triggering an Aero-dynamic Inspection just when it isneeded, thus avoiding unnecessary in-spection.

If the APM software is not used, theAerodynamic Inspection could bescheduled, for instance, at the occasionof a “C check”.

Although this approach may confirmdiscrepancies, not all may be identi-fied. In this case direct measurementsin the suspected area should be made,such as prescribed in the AircraftMaintenance Manual. This second wayis more expensive but it may offer bet-ter drag reduction results.

In a third stage, if the drag reductionseems insufficient, the airline may thenask Airbus Industrie for a PerformanceAudit.

These three approaches should helpany airline to alleviate excessive fuelconsumption.

In-board flapMiddle flap Outboard flap

All speed aileron

Spoilers 1 to 7

Trimmablehorizontalstabilizer

Rudder

Elevator

Notch flap

Krueger flap

Slats 1 to 3

Figure 3Flying control surfaces

FAST / NUMBER 2120

DETERIORATION OFAIRFRAME

AND SURFACES

The purpose of the following is to givea fuel penalty and maintenance costcomparison for the items studied.

Values given in this particular sec-tion correspond to the smaller fuelpenalties applicable to all AirbusIndustrie aircraft. They are intended tomake the reader more sensitive to fuelpenalties / maintenance cost compari-son and to sort out a few general con-clusions which pertain to all AirbusIndustrie aircraft.

Misrigging of controlsurfaces.

These items correspond to specificcontrol surfaces misrigging (seeFigure 5). They incur one of the largestfuel penalties, while the cost of the cor-rective actions, by comparison, is neg-ligible. Indeed, one spoiler extended by15mm over a 1 metre spanwise lengthleads to more than US$ 6,000 penaltyper aircraft per year (see Figure 4above). Similarly, an outboard slatmisrigging causes nearly US$ 11,000penalty per aircraft per year.Furthermore, flap misrigging - or espe-cially rudder misrigging - can lead to aslightly lower, but still considerable,fuel penalty. Another sensitive itemwhich is generally forgotten is mis-alignment at a flap track fairing whichmay cost nearly US$ 1,000 per aircraftper year.

The Aerodynamic Inspection couldbe done in flight, simply by a visual in-spection from the passenger compart-ment and by photographing control

surfaces by means of a telephoto orzoom lens.

For a misrigged control surface, theassociated corrective action cost isnegligible and should indeed be under-taken.

Absence of sealson movable sections

Seals on movable sections are very im-portant and should not be forgotten.The spanwise slat seals are mandatoryfor the optimisation of the wing super-critical airfoil. One metre of missingseal incurs a penalty of US$ 2,300 peraircraft per year. The chordwise flapseal, which may seem to have a rathernegligible effect, causes more thanUS$ 3,000 extra cost per aircraft peryear. However, the worst penaltywould result from a missing fairing

Penalty in US$ gallons per year Penalty in US$ per year Aircraft Corrective actionControl surface Excess gap Excess gap Maintenance Men M/h Cost

5mm 10mm 15mm 5mm 10mm 15mm Manual (US$)

Slat 1 (per metre) 3,850 6,100 9,150 2,310 3,660 5,490 27 80 00 2 5 25027 81 00

Slat 2 (per metre) 5,190 8,220 12,330 3,110 4,930 7,400 27 80 00 2 5 25027 81 00

Slat 3 (per metre) 7,700 12,200 18,300 4,620 7,320 10,980 27 80 00 2 5 25027 81 00

Flap 810 1,490 2,060 490 890 1,230 27 51 00 2 6 30027 54 00

Spoiler 3,060 6,850 10,220 1,840 4,110 6,130 27 61 00 1 2 10027 62 00

Aileron 810 1,500 2,120 490 900 1,270 27 11 00 1 3 150

Rudder 1,350 2,350 3,550 810 1,410 2,130 27 21 00 2 4 20027 24 00

Misalignment at 680 1,360 1,700 410 820 1,020 05 25 30 2 5 250 flap track fairing

Damaged chordwise flap seal

Figure 4Cost of misrigged flying control surfaces (A300/A310)

FAST / NUMBER 21 21

Slat

Flap, aileron, rudder

Spoiler

Excess gap

Correct dimension

Slat at 15° (gate 2) position

Excess gap

Figure 5Misrigging of control surfaces

FAST / NUMBER 2122

and rubber seal at the fin/fuselage junc-tion (US$ 3,500 ).

The check can be done from theground during the AerodynamicInspection, preferably with extendedcontrol surfaces. With retracted controlsurfaces, the same check could be doneby analysing leakage traces on thewing surface below the seals.

The associated corrective actioncosts are negligible and such actionshould be scheduled.

Missing parts

Missing parts are given in theConfiguration Deviation List showingmissing parts which must be replacedas soon as possible. A missing accessdoor can cost over US$ 6,000 per yearwhich provides adequate motivation tominimise the period of loss.

Mismatched doors

A step on the forward fuselage surfaceis much more penalising than one on

the rear. Misalignment of for-ward doors must be monitoredvery carefully; a 10mm forwardcargo door step imposes a US$2,300 annual penalty, althoughthe associated corrective actioncosts US$ 650.

During the AerodynamicInspection, the door can bechecked by standing under itand observing the line where itmeets the fuselage. Due to pres-surisation, the cabin door mustbe slightly out of flush with thefuselage. In other words, thedoor must be 2-3 mm inside thefuselage when checked on theground (see MaintenanceManual).

The decision - to repair or not- is not easy, knowing that anestimated rigging cost could bemuch higher, especially if insuf-ficiently skilled personnel areavailable.

The decision is a matter ofjudgement by each operator.

Missing door seal section

A missing door seal section has two ef-fects: it disturbs the external flow andcauses a slight leakage which has to becompensated for by an increase in en-gine compressor air bleed. In additionto the fuel penalty, a stress-provokinglow-frequency whistling sound is audi-ble in the cabin which could possiblyannoy passengers.

Preferably, the inspection should bedone with the door opened, looking fordamaged sections of the seal. With aclosed door, the same verification

could be done simply by analysing dirttraces on the fuselage.

Since this leakage may increase withtime, even if corrective actions arequite expensive, this work should beimplemented to remove the risk of fur-ther deterioration which would lead tothe aircraft being grounded eventually.

Surface deterioration

Skin roughness

Surface deterioration can lead to sig-nificant fuel penalties, especially if theskin is rough or dirty. For a completeaircraft - in the worst case - the penaltycan be as high as US$ 60,000 per air-craft per year. Another serious penaltywould certainly be on the airline’scommercial image!

Mismatched access door

Missing seal

Skin roughness

FAST / NUMBER 21 23

Skin dents

Simple dents also cause some fuelpenalty which are not costly in termsof fuel consumption (US$ 100 per air-craft per year in the worst case) but arevery expensive to repair. If the dent iswithin the Structural Repair Manualtolerances, no action is necessary forpurely aerodynamic reasons.

With repeated «loaders’ assaults»,scuff plates are frequently dented andgenerally present a step, generatinghigh fuel penalties, but corrective ac-tions are not particularly time-consum-ing.

Unfilled butt joint gap

Unfilled butt joint gaps in aircraft skinsare not very expensive in terms of ex-cess fuel consumption ( US$22 per air-craft per year in the worst case).

CONSEQUENCES OF HASTY REPAIRS

Sometimes, in an operational environ-ment, the purpose of a repair is simplyto keep the aircraft in service and toavoid grounding it. Repairs may havebeen done without taking into accountthe consequences of increased fuelconsumption.

Overfilled butt joint gap

If a butt joint gap is overfilled, thepenalty can be significant on the wingupper surface ( US$330 ). A repairwhich is not properly carried out canlead to a heavier fuel penalty than ex-isted prior to the repair (from US$14per aircraft per year for an unfilled buttjoint gap to US$500 for an overfilledgap on the upperwing in the sensitivezone 1).

External repairs

In the same way, external patches in-duce more drag, especially on the wingupper surface ( US$640 ). It is nor-mally difficult to replace an externalpatch by an internal one, but if accesshas already been gained during an in-spection, installing an internal patchcould be preferable, since it also hasless impact on an airline’s commercialimage.

Paint peeling

On the other hand, for visually improv-ing the commercial image, some fleetsare often hastily repainted withoutbothering to properly prepare the sur-face. Additional paint layers cause in-creased aircraft weight and the surfaceis less smooth due to paint steps. Over

a short time, paint may peel, with dra-matic drag effects, and severe risk ofcorrosion.

In order to prevent paint problems,proper preparation has to be carried outbefore any refresher coat is applied.

Manhours for painting have also tobe determined with great care becauseground time due to paint drying hasmuch more effect on aircraft operationthan the simple manhour cost by itself.

Dented scuff plates

External repair

Paint peeling

▲

FAST / NUMBER 2124

ENGINE COWLING

The engine cowling, due to its locationin a very sensitive zone, has to be ob-served with great care during theAerodynamic Inspection.

All surface discrepancies incur con-siderable drag .

Another item, which is less obviousbecause it is hidden, is the reverserdoor seal. The associated fuel penaltyis very large and it can be observed byleakages on the engine cowling.

For copies of the complete document, please contact AIRBUS INDUSTRIE headquarters, Customer Services Directorate, Flight Operations Support Department, Mr Jean-Jacques Speyer, Manager Operational Evaluation1, rond-point Maurice Bellonte, 31707 BLAGNAC Cedex - Tel: +33 (0)5 61 93 30 02 / 30 91 - Fax: +33 (0)5 61 93 29 68 / 44 65

CONCLUSION

The purpose of presenting the foregoing examples is simply to make operators and maintenance personnel more aware ofdrag-induced performance degradation on normal day-to-day operation.

Manhours for structural repairs must be determined with great care because significant differences exist, mainly dependingupon the exact location of the deterioration. All these discrepancies can be observed very easily from the ground during theAerodynamic Inspection.

It has been shown that many, but not all, aerodynamic degradations can be easily detected and cost-effectively repaired.The Aerodynamic Inspection will identify all of these degradations.

It ultimately becomes a matter of judgement for the airline to decide whether to rectify a fault or to ignore its effect.Nevertheless, all maintenance and operations personnel should be aware of fuel penalties which may stem from misriggedcontrol surfaces, defective seals and the lack or aircraft cleanliness - especially at or near leading edges and forward sectionsof the aircraft.

Airbus Industrie is convinced that prevention is better than repair. Continuously monitoring aircraft aerodynamic effi-ciency, together with timely rectification of problems, is, without a doubt, the best approach to minimising unnecessary fuelconsumption. ■

As a guide through this sometimes complex subject we can takesome advice from the English traveller, Rudyard Kipling:

‘I keep six honest serving men(They taught me all I knew);Their names are What and Why and WhenAnd How and Where and Who’

In this article Kipling’s servants will be employed to illustrate therange of spares issues facing an airline today.

FAST / NUMBER 21 25

by James Rutledge , Manager Marketing, Materiel Support CentreAirbus Industrie, Customer Services Directorate

FAST / NUMBER 2126

Airframe consumedspares

Airframespares float

Engineconsumedspares

Enginespares float

Fuel

Airframe price

Insurance

Flight Crew

Operational fees

Labour

Acquisition cost (depreciation & finance)

Operating expenses

Spares holding and handlingSpares

administration

Station and ground expenses

Passenger services Ticketing, sales and promotion

General and administration

Direct Operating Costs Indirect Operating Costs

Inthis article, Airbus Industriewith its considerable experi-ence of airline needs, offers:

● help to reduce Initial Provisioninginvestment by 30%,● to arrange spares access solutions tosuit an airline’s business objectives,● to assist reduce airline cycle timesand assist repair and warranty manage-ment,● dedicated heavy maintenance sup-port,● help to reduce aircraft DirectOperating Cost (DOC) by 2% throughspares rationalisation.

In response to its customers’ chang-ing business environment,AirbusIndustrie has already:● reduced its proprietary 1997 sparesprices to 1991 levels,● negotiated with major suppliers tominimise or freeze their price escala-tions,● developed Just-In-Time deliveryschemes to reduce leadtimes to a mini-mum,● guaranteed its shop repair processingtimes backed-up by no-cost forwardexchanges,● introduced a dedicated supplier ser-vices support team.

WHAT ARE SPARES?

Apart from being widely noticed as asignificant cost, spares tend to be per-ceived very differently by different de-partments within a classical airline or-ganisation.

● Senior management & Finance see spares as:✔A necessary evil✔An asset on the balance sheet✔An excess on the profit and lossaccount.● Engineering are concernedabout:✔Aircraft dispatch on time from

the hangar,✔Line maintenance,✔Never enough spares● Flight Operations experience:✔Lack of spares✔Nuisance of Aircraft deferred

defects ✔Operational interruptions● Inventory focus on:✔Satisfying maintenance needs✔Budget control✔Managing rotable, expendable

or consumable spares.● Commercial worry about:✔Passenger irritation✔Airline image✔Delays.

So who is responsible for the man-agement of all this expense, irritationand frustration? The Supply depart-ment of course! Their task is to bal-ance the wishes and service-level re-quirements of all departments of theairline against their own business ob-jectives, planning and budget. The sup-ply manager has probably achieved thebest balance when all the other depart-ments are slightly dissatisfied with him!

Spares Costs can be found in Direct and Indirect Operating Costs

WHY SPARES?

Ninety-nine percent of Airbus aircraftline replaceable parts -those listed inthe aircraft Illustrated Parts Catalog(IPC)- are subject to on-conditionmaintenance. This effectively meansyou have no guarantee of when, whereand with what consequences they mayfail. You only know that one day a partwill fail in service, and in line withMurphyʼs Law, this will probably beon a Friday afternoon and probablywith a VIP or someone from the mediaon board. And when it happens thesupply department takes a spare partfrom the store or, if none is available,loans, leases, or buys one.

Spares Benefits:operational insurance

The spare parts holding can be com-pared to an insurance policy coveringthe risk of operational disturbance. Thebenefits are a quick recovery from adamaging delay, passenger comfortloss or safety risk. However, it shouldbe stated at this point that of all air-line recorded technical delays, non-availability of spares is on average re-sponsible for not more than 10% ofthem. The cost-benefit and dollar re-turn on an investment in spares insur-ance is very difficult to measure.

To demonstrate the insurance idea,Airbus Industrie would like to intro-duce the concept of redundant or dor-mant inventory. This may be definedas the difference between the sparesbought and those used during mainte-nance. The industry standard methodof recommending spares results in theinvestment in spares increasing expo-nentially with the desired protection.This then leads to a vast increase in thelevel of redundant inventory. Todayairlines, in conjunction with the manu-facturers, look for less and less invest-ment in spares as an attempt to controlthis redundancy.

WHEN TO HOLD SPARES?

Only when you need them!In an ideal world that would be the an-swer with all things being equal, ex-cept they rarely ever are! The demandpattern for spares is erratic - a non-linear function of human inputs, tech-nical faults, and logistical constraints:● What is the problem - is it a compo-nent failure? (judgement, skill/training,availability of necessary diagnostictools).● Do we have a spare - if we have,take it, if not, do something else (rob,borrow, substitute aircraft, defer, checkthe manual, see if the problem is some-where else etc.)● Having bought an additional spare

the airline is stuck with it even if fur-ther demand may not justify the cost.● Logistics of spares on the line -where is the store (far away?), is therea storeman, do they have transporta-tion? Car, bicycle or foot? The differ-ence may be recordable delay.

The answer to this problem lies inhaving access to the right spareswhen you need them. Airbus Industriecan help provide this access.

HOW MANY SPARES?

The method used widely in the indus-try today for the calculation of theInitial Provisioning (IP) recommenda-tion for Rotable components (ie. thosewhich are considered to be repairablefor the entire life-time of the aircraft) isas follows: ● Estimating the expected or averagenumber of further on-aircraft failureswhich may occur for a part during theperiod after an initial removal has hap-pened and while the failed part is awayfor repair, ie. during the repair turn-around time.

This is calculated using the follow-ing formula:

E =

fh x n x N x 1 x TATMTBUR x 365

where:• E = the expected number of removalsresulting from the calculation,• fh = the flight hours per year per air-craft,• n = the number of units per aircraft

FAST / NUMBER 21 27

• N = the number of aircraft operating, • and TAT = the turnaround time, i.e.the time taken from removal of thefailed part from the aircraft until is isavailable for re-use after repair.

This formula therefore takes into ac-count the fact that the part is repairableand so the coverage needed is when thepart is out for repair. The TAT is there-fore a very important parameter. It alsoassumes spares coverage for the firstfailure. This point is often overlooked.● With the expected demand, a recom-mended quantity for each part is calcu-lated using Normal or Poisson proba-bility distribution tables. Using aprobability curve: if E is the averagenumber of failures then how manyparts (R) do I need to stock to ensurethat 90% of the time I will have a sparein the store. Conversely, to ensure thatonly 10% of the time I will have nospare available.

The number of spares required canbe reduced through managing themaintenance cycle for spares removedfor repair. The airline controlled part ofthe cycle involves the removal, ship-ping to repair station, and the return tostore after repairs. Within the repaircycle, opportunities exist for reducingthe spares requirement through controlof the Shop Processing Time.

Airbus Industrie offers guaranteedshop processing times not averageshop processing times and offersfree of charge loans or exchange ofreplacement spares if it does notmeet this guarantee.

The demand for Expendable parts,items such as nuts, bolts, filters, lenses,bulbs and washers is predicted using asimilar formula where the leadtime issubstituted for the TAT as it is theleadtime which determines the floatquantity.

Addressing materiel consumptioncost, Airbus Industrie is attackingspares prices (see graph below) aswell as reducing customer sparesholdings through pioneeringCustomised Lead Time (CLT). CLTproject is to supply parts as andwhen needed. This can be from 2hours to 2 years depending on theoperators’ needs. The aims of this project are:● To save cost for the customersthrough reduced storage costs andinvestment in safety stock.● To save cost through reducedholding of Airbus Industrie propri-etary parts for insurance purposes.● Flexible customer orientation.

In paraleel over 80% of AirbusIndustrie suppliers have eitherfrozen prices or held escalation be-low 2% each year since 1994 andhave committed to continue thispolicy until 1999. Working togetherwith its suppliers, Airbus Industrieis committed to keeping down thecost of ownership of the fleet.

WHERE TO ACCESS SPARES?

In the previous sections we have shownhow the in-service demand for spares isnon-linear, erratic and hard to predict,and subsequently how suppliers andoperators try, despite the difficulties, toactually forecast spares’ demand.

The result is a large investment inaircraft spares worldwide. Industrystudies report this at USD 45 billionwith a holding cost of 20% per annum.This involves a huge cost and wastethrough duplication and inefficiencies.

The key to optimisation of the sparesinvestment is balancing the cost against

FAST / NUMBER 2128

Growth index

10087 88 89 90 91 92 93 94 95 96 97

110

120

130

140

150US indices Airbus Industrie Major competitor

Escalation comparison 1987-1997 - Spares pricing baseline

Airbus customers pay 1991 prices for 1997 proprietary parts!

CONCLUSION

To conclude one can quote, again, Rudyard Kipling from his poem to the despairing Supply Manager:“ If you can keep your head when all about you

are losing theirs and blaming it on you...”...then you’ll optimise your spares holding and keep your costs down. ■

FAST / NUMBER 21 29

Mini IP package• Standardised entry-into-service stocks

• Minimum investment• Quick leadtime

Inter-airline pooling means pooling between two or more airlines

• Airline experience shared• Spread of cost

• Mutual interest relationship• Spares off-site

Brokered access to suppliers• Pooling benefits

• Fixed cost of maintenance• Partial bilateral

• Spares off-site• Subcontracted spares maintenance

• Centralised support

Consignment stocks• Pay on use

• Deferred investment• Eventual ownership by airline

• Non optimal

Airline/Vendor bilaterals• Strong relationship with vendor

• Possible Flight Hour maintenance• Mutual interest relationship

• Pooling benefits• Increased complexity

Third-party support• Flight Hour rate

• Off balance sheet financing• Spares and maintenance support

• Transfer of experience and technology

Lease means operating or financial lease of spares packages

• Off balance sheet financing• Fixed monthly lease fee

• Spares on site• Airline responsible for maintenance

Spares direct purchase• Capital commitments on balance sheet

• High negative cash flow in first year• Cost and risk of spares ownership

• Know spares availability• Total cost advantage over lease

the risk of operational interruption andso relates to spares access. Ideally thismeans having the right spares when andwhere you need them and being able togive them back afterwards!

There are several different ways ofsolving the spares access problem, of-fering various advantages - financial,experience, demand-smoothing, strate-gic or flexibility.

Airbus Industrie can help operatorsobtain access to spares when neededthrough one of the above schemes.

AND FINALLY WHO?

Within Airbus Industrie, the MaterielSupport Centre in Hamburg is respon-sible for the management of materielsupply to Airbus customers. Distribu-tion is assured from five stores aroundthe world, located at Hamburg,Washington, Singapore, Beijing andthe newly opened Frankfurt store.Together they hold 130 000 AirbusIndustrie Proprietary part numbers.

In addition to Airbus Industrie

Proprietary Parts, there are numerousvendor parts installed on Airbus air-craft. Airbus Industrie is not the primesupplier of vendor parts. Taking a posi-tive step towards cutting the cost ofownership of its aircraft, AirbusIndustrie decided in 1989 to cease be-ing the ‘middle man’ between vendorand customer. Instead, the vendor asthe principal source of spares, providesthe first line of supply and support.Nevertheless, Airbus Industrie will stillprovide the service if requested.

Other than the Original EquipmentManufacturers, there are a number oforganisations which offer partial or to-tal support for spares maintenance.These offer lease of spares, access tospares pools as well as componentmaintenance.

These organisations are typically air-line maintenance divisions offeringthird party support or dedicated sparesmaintenance centres. Airbus Industrieprovides assistance to operators to findthe optimum solution for their sparesneeds.

s of the 1st of January 1997, Airbus Industrie has opened a new distri-bution centre in Frankfurt for large high cost spares. The new bondedstore is located within the international airport at Frankfurt, one ofEurope’s busiest passenger and freight hubs. This enables Airbus

Industrie to offer a faster, lower cost, round-the-clock response to our customers’needs for their spares.

The new store holds over 600 large spare parts including, among others, the partstraditionally known as ‘Insurance Items’. Parts stored are for example passengerand cargo doors, wingtips, flaps, slats, leading edges, and elevators. In all, there aresome 392 part numbers held in this store. All parts are available for sale, exchangeor lease to Airbus operators as and when required, saving the cost of having to pur-chase and store these bulky items “just-in-case”.

The opening of the Frankfurt store is yet another Airbus Industrie initiative to re-duce the cost of ownership of Airbus aircraft. ■

A

FAST / NUMBER 2130

irbus Industrie will be holding its 4th Materiel Symposium inSeptember. This symposium carries on the tradition of meeting withalmost the entire Airbus operator and supplier community to discussmateriel issues.

The theme of this year’s symposium is

‘COST SERVICE BALANCING, LET’S KEEP UP THE MOMENTUM’

reflecting the on-going pressure on the materiel supply chain to deliver more ser-vice while keeping costs down.

Through these Materiel Symposiums Airbus Industrie obtains first hand knowl-edge of the problems and concerns of Airbus operators which is a major drivingforce in its efforts to serve its customers. Invitations are being sent to all our cus-tomers and suppliers to attend what, we believe, will be another dynamic and pro-ductive programme. ■

A

FRANKFURT STOREEXPANDING OUR SERVICES

FrankfurtWashington

Hamburg

Beijing

Singapore

4TH MATERIEL SYMPOSIUM15TH TO 17TH OF SEPTEMBER 1997, KUALA LUMPUR

FAST / NUMBER 21 31

Aerodynamic deterioration

The British airship R-33 which was torn awayfrom its mooring mast in a storm in 1925.A small crew were on board and managed to bring the airshipback to its base, but it took them 29 hours.

RESIDENTCUSTOMERSUPPORTREPRESENTATIONMohamed El-Boraï, Vice President Customer Support Services DivisionTelephone: +33 (0)5 61 93 35 04 / Telefax: +33 (0)5 61 93 41 01Jean-Paul Gayral, Resident Customer Representation Administration DirectorTelephone: +33 (0)5 61 93 38 79 / Telefax: +33 (0)5 61 93 49 64Airbus Industrie headquarters1 rond-point Maurice Bellonte, 31707 Blagnac Cedex France

32 FAST / NUMBER 21

LOCATION COUNTRY TELEPHONE TELEFAXABU DHABI United Arab Emirates 971 (2) 706 7702 971 (2) 757 097 AMMAN Jordan 962 (8) 51 284 962 (8) 51 195 ATHENS Greece 30 (1)981 8581 30 (1) 983 2479 BANGKOK Thailand 66 (2) 531 0076 66 (2) 531 1940BEIRUT Lebanon 961 (1) 629 125 Ext. 2687 961 (1) 601 200BOMBAY (MUMBAI) India 91 (22) 618 3273 91 (22) 611 3691BRUSSELS Belgium 32 (2) 723 4824 32 (2) 723 4823BUCHAREST Romania 40 (1) 312 6670 40 (1) 312 6670 BUENOS AIRES Argentina 54 (1) 480 9408 54 (1) 480 9408 CAIRO Egypt 20 (2) 418 3687 20 (2) 418 3707CHENGDU Peoples Republic of China 86 (28) 570 385 86 (28) 521 6511CHICAGO USA (Illinois) 1 (773) 601 4602 1 (773) 601 2406COLOMBO Sri Lanka 94 73 2197 / 2199 94 (1) 253 893 DAKAR Senegal 221 201 615 221 201 148 DAKHA Bangladesh 880 (2) 896129 880 (2) 896130DELHI India 91 (11) 565 2033 91 (11) 565 2541 DETROIT USA (Michigan) 1 (313) 247 5090 1 (313) 247 5081DUBAI United Arab Emirates 971 (4) 822 519 971 (4) 822 273 DUBLIN Ireland 353 (1) 705 2294 353 (1) 705 3803 DULUTH USA (Minnesota) 1 (218) 733 5077 1 (218) 733 5082DUSSELDORF Germany 49 (211) 9418 687 Ext. 751 49 (211) 9418 035FRANKFURT Germany 49 (69) 696 3947 49 (69) 696 4699GUANGZHOU Peoples Republic of China 86 (20) 8612 8808 86 (20) 8612 8809GUAYAQUIL Ecuador 593 (4) 290 005 Ext. 143 593 (4) 293 685HANOI Vietnam 84 (48) 731 613 84 (48) 731 612HO CHI MINH CITY Vietnam 84 (8) 84 57 602 84 (8) 84 46 419 HONG KONG Hong Kong 852 2747 8449 852 2352 5957 ISTANBUL Turkey 90 (212) 574 0907 90 (212) 573 5521 JAKARTA Indonesia 62 (21) 550 1993 62 (21) 550 1943 JEDDAH Saudi Arabia 966 (2) 684 2864 966 (2) 685 7712 JOHANNESBURG South Africa 27 (11) 978 3193 27 (11) 978 3190 KARACHI Pakistan 92 (21) 457 0604 92 (21) 457 0604 KINGSTON Jamaica 1 (809) 924 8057 1 (809) 924 8154KUALA LUMPUR Malaysia 60 (3) 746 7352 60 (3) 746 2230 KUWAIT Kuwait 965 474 2193 965 434 2567 LARNACA Cyprus 357 (4) 643 181 357 (4) 643 185 LISBON Portugal 351 (1) 840 7032 351 (1) 847 4444 LONDON (LHR) England 44 (181) 751 5431 44 (181) 751 2844 LOS ANGELES USA (California) 1 (310) 342 8904 1 (310) 578 9012 LUTON England 44 (1582) 39 8706 44 (1582) 48 3826 MACAO Macao 853 898 4023 853 898 4024MADRID Spain 34 (1) 329 1447 34 (1) 329 0708

33FAST / NUMBER 21

LOCATION COUNTRY TELEPHONE TELEFAXMANCHESTER England 44 (161) 489 3155 44 (161) 489 3240MANILA Philippines 63 (2) 831 5444 63 (2) 831 0834 MAURITIUS Mauritius 230 637 8542 230 637 3882MEMPHIS USA (Tennessee) 1 (901) 797 6050 1 (901)797 6030 MEXICO CITY Mexico 52 (5) 784 3874 52 (5) 785 5195 MELBOURNE Australia 61 (3) 9338 2038 61 (3) 9338 0281 MIAMI USA (Florida) 1 (305) 871 1441 1 (305) 871 2322 MINNEAPOLIS USA (Minnesota) 1 (612) 726 0431 1 (612) 726 0414 MONTREAL Canada 1 (514) 422 6320 1 (514) 422 6310 MOSCOW Russia 7 (095) 753 8061 7 (095) 753 8006 MUSCAT Oman 968 521 286 968 521 286NAIROBI Kenya 254 (2) 822 763 254 (2) 822 763 NEW YORK USA (New York) 1 (718) 656 0700 1 (718) 656 8635 NUREMBERG Germany 49 (911) 365 6219 49 (911) 365 6218PARIS (CDG) France 33 (0)1 48 62 08 82 / 87 33 (0)1 48 62 08 99 PARIS (ORY) France 33 (0)1 49 78 02 88 33 (0)1 49 78 01 85 PHOENIX USA (Arizona) 1 (602) 693 7445 1 (602) 693 7444PORT OF SPAIN Trinidad & Tobago 1 (809) 669 1647 1 (809) 669 1649 PRAGUE Czech Republic 420 (2) 316 4727 420 (2) 316 4275 PUSAN South Korea 82 (51) 971 6977 82 (51) 971 4106 ROME Italy 39 (6) 6501 0564 39 (6) 652 9077 SAN’A Yemen 967 (1) 344 439 967 (1) 344 439SAN FRANCISCO USA (California) 1 (415) 634 4375 1 (415) 634 4378 SAN JOSE Costa Rica 506 (4) 417 223 506 (4) 412 228 SEOUL South Korea 82 (2) 665 4417 82 (2) 664 3219 SHANGHAI Peoples Republic of China 86 (21) 6268 4122 86 (21) 6268 6671 SHANNON Ireland 353 (1) 705 2084 353 (1) 705 2085 SHENYANG Peoples Republic of China 86 (24) 272 5177 86 (24) 272 5177SINGAPORE Singapore 65 (5) 455 027 65 (5) 425 380 TAIPEI Taiwan 886 (3) 383 4410 886 (3) 383 4718 TASHKENT Uzbekistan 7 (37) 1254 8552 7 (37) 1255 2878 TEHRAN Iran 98 (21) 603 5647 98 (21) 603 5647 TOKYO (HND) Japan 81 (3) 5756 5081 81 (3) 5756 5084

81 (3) 5756 8770 81 (3) 5756 8772TORONTO Canada 1 (905) 677 8874 1 (905) 677 1090 TULSA USA (Oklahoma) 1 (918) 292 3227 1 (918) 292 2581 TUNIS Tunisia 216 (1) 750 639 216 (1) 750 855 VANCOUVER Canada 1 (604) 276 3776 1 (604) 276 3548 VIENNA Austria 43 (1) 7007 3688 43 (1) 7007 3235 WINNIPEG Canada 1 (204) 985 5908 1 (204) 837 2489 XIAN Peoples Republic of China 86 (29) 870 7651 86 (29) 870 7255ZURICH Switzerland 41 (1) 812 7727 41 (1) 810 2383