a380 mpd & base maintenance analysis...the oldest a380 aircraft are now approaching the end of...

AIRCRAFT COMMERCE ISSUE NO. 117 • APRIL/MAY 2018

36 IMAINTENANCE & ENGINEERING

The A380-800 began operationalservice in October 2007 withSingapore Airlines. The oldestA380s are now approaching the

end of the first cycle of maintenanceinputs covering a 12-year (YE) period.

The A380 was the first Airbus toenter service on a 24-month (MO) basecheck interval. This equates to a six-checkcycle over 12 years, rather than the morefamiliar 18MO base check interval, eight-check cycle. The application of moderndesign tools and principles in earlydevelopment of the aircraft systems andconstruction materials played a key rolein optimising maintenance efficiencies.

As of the end of 2017, airlines canescalate the 24MO base check cycle to36MO, so that aircraft move to a four-check cycle over 12YE. This will alloweven greater planning flexibility andincrease in-service revenue for the fleet.

The traditional lighter structuralinspection at six years, and a heavystructural check interval of 12YE, willstill slot into either the four- or six-checkcycle at 72MO and 144MO.

The A380 maintenance planningdocument (MPD) uses a variation offlight hour (FH), flight cycle (FC) and/orcalendar intervals to optimise utilisationof each individual scheduled maintenancetask. An increase from 24MO to 36MOfor maintenance inspection tasks,therefore, requires equivalent FHescalations from 12,000FH to 18,000FH.

Base check escalations are a result ofpositive in-service data collection, andfollow escalation of the A checks from750FH to 1,000FH in 2016. The 24MOcheck cycle currently in use, the move toa 36MO check cycle, and the loomingfirst 12YE checks are examined here.

Fleet overview As of mid-April 2018, there are 224

A380-800s, with 220 in active serviceacross 13 airlines, and four in storage.

The stored aircraft are with Doric AssetFinance (3) and Singapore Airlines (SIA)(1), two of which are undergoing end-of-lease maintenance inputs (see A380 table,page 37).

The oldest aircraft in active service isserial number (S/N) 007, just over 12years old, which was originally listedwith Airbus, and then delivered toEmirates Airline in 2009.

The highest FH aircraft is S/N 015with 41,761FH operating for QantasAirways, at nearly 10 years old.

The highest FC aircraft is S/N 009with 5,824FC operating for Emirates, atnearly 11.5 years old.

Engine options for the fleet includethe Trent 970-84/970B-84, referenced asA380-841; the Trent 972-84/972B-84,referenced as A380-842; and the EngineAlliance GP7270 referenced as A380-861.

Of the 13 airlines, seven have theTrent 970 engine option, one has theTrent 972 engine, five have the GP7270engine, and only Emirates has twooptions in the fleet with the GP7270 andTrent 972.

From statistics available, discountingaircraft less than 1.5 years old for moreaccurate annual utilisation statistics, theaircraft have only a minor variation inaverage FH usage of 4,381FH for the AirFrance fleet, to 5,491FH with EtihadAirways.

The average range of annual FC usageis from 429FC, for the Qantas fleet, up to624FC for the Qatar Airways fleet.

As always, geographical location andindividual airline operational use of thefleet range/versus capacity of passengermovement results in a variation in the FHto FC ratio. The lowest average FH:FCratio is 7.3:1 for Emirates; the highestFH:FC ratio is 11.8:1 for Qantas.

China Southern Airlines, MalaysianAirlines and SIA have incomplete FH andFC data to add to the utilisation survey.

Emirates has by far the largest fleet

with over 100 aircraft. As some aircraftare configured for regional use and othersfor longer-distance routes, Emiratesaircraft show the largest range in annualFH utilisation, from just over 3,200FH toa little more than 5,200FH.

The fleet’s average annual utilisationis in the region of 4,725FH and 560FC.

A380 MPD The A380 MPD combines mandatory

repeat scheduled maintenance inspectionsrequired for continued airworthiness ofthe aircraft. This includes scheduledmaintenance tasks in airlines’ ApprovedMaintenance Programmes (AMP).

Revision 13 of the MPD was releasedon 1 February 2017, and contains the Acheck interval escalation from 750FH to1,000FH. It also contains the taskinterval parameters supporting thecurrent 24MO base check cycle patternused by in-service aircraft not trialling the36MO escalations.

The most recent revision to the MPD,Revision 14, was released in late 2017. Itcontains the escalation of specific taskintervals to coincide with progression to a36MO/18,000FH base check cycle.

Revision 13 of the MPD contains1,817 tasks listed under the three mainsections of Systems (including auxiliarypower unit (APU) and Powerplant),Structure, and Zonal. Aircraft andcomponent FH, FC and calendar time areused for the main threshold and repeatinterval operational parameters. Calendartime is covered by Hour (HR), Day (DY),MO and YE.

Additional operational parameterswill be affected by the local regulatoryauthority the aircraft operate under, orare contained within additional vendordocumentation. In this event the MPDreferences the threshold or interval asNational Requirement (NR), VendorRequirement (VR) or ‘NOTE’, which isused to reference further information,

The oldest A380 aircraft are now approaching the end of their first basecheck cycle over a 12-year period. Positive maintenance inspection resultsa check cycle, releasing the aircraft for longer periods of operationalavailability. Sandra Everest examines the A380’s base maintenance inputs.

A380 MPD & basemaintenance analysis

including interval detail contained withinthe individual task description.

Many inspection tasks within theMPD originate from other sourcedocuments, such as the MaintenanceReview Board Report (MRBR), and theAirworthiness Limitation Section (ALS)programmes that monitor damagetolerance and certification maintenancerequirements (CMRs). Information fromregulatory authorities, such asairworthiness directives (ADs) andoriginal equipment manufacturer (OEM)service bulletins (SBs) also feeds into theMPD.

The current referenced Limit ofValidity (LOV) or maximum FH/FCaircraft utilisation covered by the MPD(and source documents) is 19,000FC or140,000FH. For a high FC utilisationaircraft this equates to an operationalservice of 28 years, while for a high FHutilisation aircraft it equates to 25 years.

Task interval optimisation The A380 does not use the industry

familiar letter checks within the MPD.Under the MPD up to Revision 13, letterchecks are large groupings of inspectionat equal intervals of 24MO. They maystill commonly be referred to as a cycle ofC1, C2, C3, C4, C5 and C6 checks (seetable, page 38). The traditional style oftask grouping into pre-defined checks isreplaced by the concept of recognising the

inherent reliability in each of the aircraft’ssystem and structural components.

“At the beginning of the A380’smaintenance programme development, adecision was made to stop using thecheck, and apply a usage parameter ofFH and FC,” explains Pierre Salles-Parfouby, head of the A380 maintenanceprogramme at Airbus. “The aim of thiswas to give more flexibility to airlines inorganising their maintenance planning, sothat they can perform maintenance whenthe aircraft stops, rather than stop theaircraft to carry out maintenance.”

The design of the A380 hasmaximised maintenance programmeinterval efficiencies.

“There are several examples wherethe aircraft’s system design was a first forcommercial aircraft,” adds BertholdStegerer, head of aircraft operationsmarketing at Airbus. “This included anintegrated modular avionics system,which has reduced the number ofstandalone computers, a 5,000PSIhydraulic system with only two circuitsinstead of three, and aluminium wiringthat reduced the aircraft’s total weightloading on the structure.”

New construction materials alsohelped to lighten the maintenanceinspection programme. “New to theA380 was the application of GLARE,”continues Stegerer. “GLARE is acomposite material comprisingaluminium and glass fibre, with an

adhesive as a compound. Compared toaluminium alloy, GLARE provides bettercrack propagation and more corrosionresistance, allowing the MPD to berelatively light.”

For check planning assistance Airbusprovides an AirPl@n Simulator forcustomised maintenance planningsimulation. This is accomplished usingMPD man-hours (MH) based on aircraftutilisation, and is accessed through theAirbusWorld website.

The 24MO check cycle The A380 MPD was developed to

support an annual utilisation of up to6,000FH and 1,100FC. The currentaverage utilisation of the fleet in terms ofFH and FC will fall within theseparameters, so the calendar interval whenlisted with an FH or FC interval is metfirst. All other tasks with FH and FCparameters will be monitored to beinserted into the closest check, dependingon access and MH requirements.

For most of the active in-serviceaircraft, base check intervals asmentioned currently fall in multiples of24MO. A large number of 24MO tasksalso have a 12,000FH backstop. The12,000FH interval is long enough for the24MO interval to be fully utilised by alloperators, since 6,000FH in 12 months isequal to more than 16FH per day, and isunlikely to be reached by any operator.


ISSUE NO. 117 • APRIL/MAY 2018 AIRCRAFT COMMERCE

A380 FLEET OVERVIEW - IN SERVICE & STORED FLEET AGE & UTILISATION CHARACTERISTICS*

Oldest Average Average Highest HighestNumber of Engine active Average annual annual FH:FC Average Average cumulative cumulative

Airline aircraft Type aircraft age FH FC ratio FH/day FC/day FH FC

Air France 10 GP7270 9.2 7.3 4,381 484 9:1 12.00 1.33 32,528 3,905

Asiana Airlines 6 Trent 970 4.3 3.1 5,481 506 10.8:1 15.02 1.39 18,740 2,222

British Airways 12 Trent 970 5.4 4 4,606 446 10.3:1 12.62 1.22 19,449 2,219

China Southern 5 Trent 970 7.1 6.5 N/A N/A N/A N/A N/A N/A N/A

Doric* 3 Trent 970/ 11.9 11.7 4,448 492 9:1 12.19 1.35 N/A N/A

GP7270

Emirates Airline 102 Trent 972 12.2 4.5 4,498 616 7.3:1 12.32 1.69 41,124 5,824

Etihad Airways 10 GP7270 3.8 2.7 5,491 569 9.7:1 15.04 1.56 16,141 1,841

Korean Air 10 GP7270 7.4 6 4,735 429 11:1 12.97 1.18 31,268 3,172

Lufthansa 14 Trent 970 8.5 6.5 4,738 487 9.7:1 12.98 1.33 31,373 3,464

Malaysia Airlines 6 Trent 970 6.5 6 N/A N/A No/A N/A N/A N/A N/A

Qantas Airways 12 Trent 972 10.2 8.7 5,074 430 11.8:1 13.90 1.18 41,761 3,709

Qatar Airways 9 GP7270 4.6 3 5,234 624 8.4:1 14.34 1.71 15,688 2,311

Singapore Airlines* 19 Trent 970 11.1 7.1 4,709 542 8.7:1 12.90 1.48 N/A N/A

Thai Airways 6 Trent 970 6.1 5.5 5,088 611 8.3:1 13.94 1.67 24,108 3,285

International

* FLEET HAS AT LEAST ONE AIRCRAFT LISTED AS UNDERGOING LEASE RETURN CHECKS OR IS CURRENTLY PARKED.

FH AND FC INFORMATION ONLY AVAILABLE FOR SEVEN OF THE SINGAPORE AIRLINES FLEET.

FH AND FC INFORMATION FOR AIRCRAFT UNDER 1.5 YEARS OF AGE HAS NOT BEEN USED IN ANNUAL AVERAGE FIGURES.

INFORMATION CURRENT IN MID-APRIL 2018



Although letter checks are not used inthe MPD, base check and larger linechecks are still often referred to as ‘C’checks and ‘A’ checks’. For the A380, thecycle of six C checks have been at 24MO,48MO, 72MO, 96MO, 120MO and144MO. These can be genericallyreferred to as the C1, C2, C3, C4, C5 andC6 checks (see table, this page).

The larger groupings of structuralinspections tasks fall due at 72MO and144MO, which fall in line with the thirdand sixth C check.

Line checks or A checks were initiallyset at an interval of 750FH, but have nowbeen extended to 1,000FH. Using the twofigures as a range matching current fleetutilisation, A checks fall due about everytwo to two-and-a-half months.Realistically there is not a large groupingof tasks at these intervals. Line and Achecks will comprise all tasks that fallshort of the 24MO/12,000FH C checkinterval, along with all other FH and FCtasks as utilisation limits are reached.

The aircraft’s maintenance clock doesnot start at the same point for allinspection tasks. For most of thecalendar-driven interval tasks, the clockstarts at Transfer of Title (ToT) to thenew operator during the delivery process.For many of the FH- and FC-driventasks, the aircraft’s first flight starts theutilisation count. For aircraftcomponents, the first flight afterinstallation begins the utilisation orcalendar count. Alternatively, the firstflight date plus 90 days may be used ifToT occurs more than 90 days after thefirst flight. FH and FC parameter tasks,therefore, might not be as neatly alignedas might be expected.

There are also some permitted‘maximum variations’ that can be appliedto listed individual inspection intervals.For example, on tasks controlled by FC, atask with an interval of more than 500FChas an allowed variation of 5% or 250landings, whichever is least. For acalendar example, a task with an intervalof more than three years has a 3MOvariation allowance.

Tasking grouping The large groups of tasks using

multiples of 24MOs will oftenincorporate an FH and FC parameter tocover higher than average utilisation.Many tasks and task groups do not haveintervals that are exact multiples of24MO. Those with intervals betweenexact multiples of 24MO will be broughtforward and performed early. This avoidsthe aircraft being frequently grounded toperform smaller groups of tasks.

For example, on a 24MO/12,000FHcheck interval, there are nine differenttask groups with the potential to begrouped into a 24MO interval: 24MO;12,000FH; 24MO or 12,000FH,whichever comes first (WCF); 72MO or12,000FH, WCF; 11,200FH or 24MO,WCF; 1,500FC or 12,000FH, WCF;2,200FC or 12,000FH, WCF; 24MO or15,000FH, WCF; and 12,000FH or36MO, WCF. These can all broadly beincluded as one group with a dualinterval of 24MO and 12,000FH. Thesetasks come due every C check, and somay generically be referred to by some as‘1C’ tasks. For example, there are 105calendar-driven tasks in the C1 check thatapply to all A380 variants (see table, page

42). There are also other calendar-driventasks that only apply according to theaircraft’s airframe modification status(15), the variant (20 and 11), and theengine’s modification status (5).

The same method is then applied forthe additional tasks to be performed at a48MO/24,000FH interval. Groups oftasks that have 48MO and/or 24,000FHintervals will form a large quantity oftasks. They may be grouped with24,000FH or 4,400FC, WCF; 24,000FHor 72MO, WCF; 24,000FH or 36MO,WCF; 4,400FC or 48MO, WCF; and24,000FH or 48MO, WCF. These groupsof tasks might collectively be referred toas ‘2C’ tasks, and so would be performedat every second base check.

The third and fourth groups of taskscan be referred to as the 72MO, or ‘3C’;and 144MO, or ‘6C’ tasks. These are thelight structural inspection at 6YE, andheavy structural inspections at 12YE.

There are also groups of tasks that aregrouped into 96MO and 120MOintervals. These might be referred to ‘4C’and ‘5C’ tasks.

The number of tasks described as‘1C’, ‘2C’, ‘3C’, ‘4C’, ‘5C’ and ‘6C’ is notlisted. Instead the total number ofcalendar-driven tasks that come due inthe C1 to C6 checks are listed (see table,page 42).

In addition to calendar-driven tasks,there are FH and FC tasks with variousintervals that come due during the 24MOA check cycle interval, the first 12-yearbase check cycle, after the first 12-yearbase check cycle, or are VR tasks (seesecond table, page 42). As an example,there are 143 A check tasks that apply toall A380-800s, and 530 tasks that applyto all A380-800s in the first base checkcycle. As these tasks do not have calendarintervals in exact multiples of 24MO, butwill come due between one of the A orbase checks depending on the aircraft’sFH and FC utilisation, they are referredto as out-of-phase (OOP) tasks. Thesewill be grouped into the appropriate A orC check according to the operator’spreferences.

It is therefore not possible tosummarise the number of tasks that willcome due in each of the A and C checks.The number of FH and FC tasks aresummarised. As an example, 530 tasksthat apply to all A380-800s fall dueduring the 12-year base check cycleAnother 26 depend on the airframe’smodification status, 39 apply to theA380-841/-842, and 36 apply to theA380-861 (see second table, page 42).

36 MO check cycle Revision 14 of the MPD supports

escalation of specific C check taskintervals from 24MO or 12,000FH, to36MO or 18,000FH, thereby avoiding

A380 MAINTENANCE PROGRAMME BASE CHECK CYCLES 24MO & 36MO C CHECK INTERVALS

Calendar MPD Approx FH Approx FCinterval FH interval per interval per

C check MO interval avg utilisat avg utilisa

1st or C1 24 12,000 9,000-10,500 1,100

2nd or C2 48 24,000 18,000-21,000 2,200

3rd or C3 72 36,000 27,000-31,500 3,300

4th or C4 96 48,000 36,000-42,000 4,400

5th or C5 120 60,000 45,000-52,500 5,500

6th or C6 144 72,000 54,000-63,000 6,600

Calendar MPD Approx FH Approx FCinterval FH interval per interval per

C check MO interval avg utilisat avg utilisa

1st or C1 36 18,000 13,500-15,750 1,650

2nd or C2 72 36,000 27,000-31,500 3,300

3rd or C3 108 54,000 40,500-47,250 4,950

4th or C4 144 72,000 54,000-63,000 6,600



one aircraft grounding and C check overeach six-year period. There will now betwo base checks instead of three in the72-month interval, and just four checksin the cycle (see table, page 38).

The A380 C checks will move to36MO or 18,000FH, 72MO or36,000FH, 108MO or 54,000FH, and144MO or 72,000FH. The largergroupings of structural inspections tasksat 72MO and 144MO will still be in linewith the second and fourth C check in acycle. That is, the C2 and C4 checks.

This check escalation has beenachieved by analysing the in-service fleetfindings down to individual task level.

“For the aircraft in service eachindividual task in terms of the escalationprogramme is looked at,” explainsStegerer. “The reports that we get backon content of the task or the potentialfindings will either lead to escalation ofthat particular task or not.”

“The path for escalating the A checksfrom 750FH to 1,000FH was secured in2016,” adds Salles-Parfouby. “The nextstep in the process was to proceed withthe C check escalation programme during2017. The result is that many of the24MO and 24MO/12,000FH tasks arebeing escalated to 36MO, equal to about18,000FH; and the 48MO tasks are beingescalated to 72MO.

“There are still some 24MO and48MO tasks where we need to collectand review more airline reports, so in themeantime the interval will not change,”adds Salles-Parfouby. “This is acontinuous process of informationcollection.”

While Airbus will retrieve all thereports from across the airlines to getindividual task escalations increasedinside the MRB Report leading into theMPD, each airline will discuss its ownreliability programme with its localauthority to obtain approval on intervalescalation.

“Two airlines are currently validatingthe 36MO base check interval throughtheir local authorities,” adds Salles-Parfouby. “Other airlines are taking intoaccount the revised MPD, based on theirneeds, organisation and timeconstraints.”

As the process of report collection isundertaken for all tasks, there is potentialto extend some larger structural taskgroupings at 6YE and 12YE.

“We still need to collect data from the72MO events,” continues Salles-Parfouby. “After only 10 years of servicethere have obviously been far fewer72MO checks than 24MO checks. Yes,the 72MO tasks could be extended withthe reports we receive from the operators,but you have to keep in mind thatincreasing the interval of 72MO willaffect the synchronisation of the 144MOcheck. With maintenance planning,synchronisation is key to avoid additionalcosts.”

For operators that choose to move tothe 36MO cycle after their maintenanceprogrammes have been validated by localauthorities, a bridging check would beperformed at the next convenient basecheck that would release the aircraft ontoa 36MO cycle.

“The check escalations have thepotential to introduce a 10% reduction inmaintenance costs when applied to themain maintenance events at 1,000FH and36MO over the 12YE maintenancecycle,” explains Stegerer.

“The main point is that the aircrafthas more potential for flexibility in themaintenance programme. Its in-servicebehaviour so far has allowed Airbus toextend intervals at an individual tasklevel,” adds Stegerer. “There is always,however, a balance to be found. Pushingfor longer intervals for the sake of it doesnot make sense, but it shows how easy itis to maintain the aircraft in terms ofground time and packaging.”

MPD content

System tasks The Rev 13 MPD Systems, APU and

Powerplant section contains 748 taskswithin about 110 different inspectioninterval groupings. These intervals useone or a combination of two FH, FC, andcalendar parameters. AH is also usedwhen referring to APU hour utilisation.

Of the 748 tasks, 242 are FH-driven,23 are FC-driven, 371 are calendar-based,and 57 are a combination of FH/FC orMO. The remaining 55 tasks are relatedto vendor or NOTE references forinterval requirements.

The Systems section inspectionsoutline aircraft systems and aircraftcomponent scheduled maintenance tasks.The term aircraft component covers theengines and APU.

Of the 748 tasks, 582 apply to allA380-800s, 48 cover the A380-841/842,35 apply to the A380-861, and 83 applyaccording to each aircraft’s modification(mod) status.

Inspections contained in the Systemssection cover 11 task codes and nine skillcodes, and originate from numeroussource documents. Task codes define thetype of task, for example: FNC for afunctional check, LUB for a lubricationtask, or DET for a detailed inspection.Skill codes define the required experienceor trade knowledge required for the task,for example: RA for radio andcommunications, CL for cleaning, orNDT for non-destructive testing. TheTask and Skill code overview is detailed(see table, this page).

Of the listed inspections, 726 have a100% interval only over 95 differentgroupings, while 22 tasks have 100%threshold over 15 different groupings. Ofthe tasks with initial thresholds andrepeat intervals, six groupings have

A380 MAINTENANCE PROGRAMME TASK CODES AND SKILL CODES VERSUS TASK QUANTITIES (MPD REV 13)

Task codes GVI DET SDI CHK SVC VCK LUB FNC OPC RST DIS Totaltasks

System 140 109 23 1 12 42 24 68 199 73 57 748Structures 113 505 260 878Zonal 191 191

GVI: General Visual Inspection, DET: Detailed Inspection, SDI: Special Detailed Inspection, CHK: Check, SVC: Servicing, VCK: Visual Check, LUB: Lubrication, FNC: Functional Check, OPC Operational Check, DIS: Discard

Skill Codes AF EN NDT AV CL LUB EL RA UT

System Section 390 122 14 63 37 17 94 6 5 748Structures Section 571 49 258 878Zonal Section 175 16 191

AF: Airframe, EN: Engine, NDT: Non-Destructive Testing, AV: Avionics,CL: Cleaning, LU: Lubrication, EL: Electrics, RA: Radio and Communications, UT: Utilities

reduced repeat intervals, and twogroupings have increased repeat intervals.

Systems section sampling tasksinclude a schedule for the operationalcheck of the cabin escape slides, peroperator’s fleet per door position (eitherside) not to exceed 36MO.

Of the large number of differentinterval groupings, more than 40intervals have only one task listing, andonly eight have more than 10 tasklistings. So, the larger groupings of tasksfall into only a limited number ofintervals forming the foundation of eachbase check event.

Not all tasks in the MPD apply to allaircraft. An applicability column lists theaircraft type for which the inspection isrequired, including the pre- or post-modification numbers, engine type andconfiguration differences.

Larger access and preparationrequirements for inspections appear in allthree Systems, Structures, and ZonalMPD sections.

For 72MO calendar-driveninspections, there are 110 tasks, 92 ofwhich apply to all aircraft, and 18 toA380-800 per mod status. There areadditional groupings of 72MO or12,000FH, 15,000FH or 8,000FC,36,000FH, and 24,000FH or 72MO.These groups include 10 higher accesstasks to be placed at the 72MO checkinterval.

Access required includes removal ofdado panels, floor panels (for drainagepipe inspections), ceiling and sidewallpanels, wing panels and cargo bay panels.

Chapter 20 of the ATA aircraftdocumentation number system covers‘Standard Practices’. A large number oftasks in the Systems section that requiredthe greatest access and preparationfigures will be Chapter 20 tasks. Theseinclude restoration by cleaning of theelectrical wiring interconnection system(EWIS) installed in the main deck andcargo bays, including utility areas wherespecified. In the 72MO check groupingthere are more than 20 Chapter 20 tasks.

For the 144MO calendar-driveninspections, 60 apply to all A380-800s,one to the A380-841/842, one to theA380-861, and one to the A380-800 permod status (applicable to crew restcompartments). Although no tasks listedin the MPD are ‘at engine removal’, theSystems section planning notes do appearto detail where tasks can be accomplishedat the opportunity of engine removal.

In the 144MO grouping there are 34ATA Chapter 20 restoration by cleaningcards (task code - RST, and skill code -CL). Most of the access will tie in withaccess gained for the Structures 144MOtasks. This includes fuel tank access forthe SFAR 88 ignition source preventionprogramme.

The Systems section contains the

largest number of VR inspection listings.There are 32 task entries, 20 of whichapply to all aircraft, and 12 to A380-800per mod status.

Most of the VR tasks relate to cabinsystems, including passenger and crewoxygen hydrostatic in-shop testing, andcabin escape facilities testing perregulatory authority request.

Another grouping of tasks without alisted threshold or interval falls under thegrouping of NOTE. This refers to theinstruction NOTE listed in the interval

column for the task. There are 20 taskswith an interval of NOTE, of whichseven apply to all aircraft, eight to theA380-841/842, and five to the A380-861.

NOTE tasks range from discardingflashlight batteries and obtaining fueltank samples, to the life-limited discardlisting for landing gears, engine parts andAPU components.

Interestingly, in Revision 13 of theMPD, there is already a large grouping of15 inspections tasks at 36MO. The tasksescalated from the 24MO/12,000FH





groupings fall due with this group. There are 112 systems tasks that will

most likely fall due before the C checks.The largest quantity grouping is the750FH group of nine tasks. The lowestfrequency tasks are at 48 hours.

Structures The Revision 13 MPD Structures

section contains 878 tasks with 530different threshold and intervalsgroupings using calendar, FH or FCparameters or a combination of intervalparameters. By far the most are FC andFH combinations.

Of the 878 tasks, three are FH-driven,83 are FC-driven, 243 are calendar-based,and 545 are a combination of either FHor FC and MO. The remaining four tasksare related to Vendor or NOTE referencesfor interval requirements.

Of the 878 tasks, 801 apply to allA380-800s, 26 to the A380-841/842, 32to the A380-861, and 19 apply accordingto the A380-800 mod status.

Inspections contained in the sectioncover only three task codes (DET, SDIand GVI) and three skill codes (AF, ENand NDT). Numerous source documentsare referenced (see table, page 40).

As well as monitoring the aircraftstructure for fatigue and accidentdamage, the purpose of the Structuresinspections includes controlling corrosionto a level 1 or better.

As a guide, if corrosion is found oninspection of the aircraft structure, it isgiven a level of 1-3 for defect reporting.Level 1 corrosion can be blended outwithin the permitted limits by theaircraft’s Structural Repair Manual(SRM) or per inspection documents used.Level 2 corrosion is reported if the area tobe blended out exceeds the permittedlimits requiring repair or replacement,while Level 3 corrosion is determined tobe of an airworthiness nature andrequires potential fleetwide inspection.

All structures tasks use an initialthreshold and repeat interval apart fromone task that has only a 100% interval.

Most of the tasks have reducedintervals in comparison to the initialthreshold. This can vary from as little as100FC less than the original threshold, tomore than halving the initial threshold.

Unlike older Airbus types, the A380MPD was not released with a separate setof thresholds and intervals for samplingaircraft which often represented apercentage of the oldest aircraft in theoperator’s fleet.

“There are no tasks in the A380’sMPD relating to the MRBR fatigue-sampling programme as in the case ofprevious aircraft maintenanceprogrammes,” explains Salles-Parfouby.“Instead, a fatigue-monitoringprogramme has been developed.Operators have benefited from more thana 90% reduction in the number of MRBRsampling tasks which feed the MPD.”

Landing gears, however, are involvedin a fleetwide sampling programmecontrolled independently of the MPD.For maintenance planning purposes,landing gears are to be removed for ‘off

A380 MAINTENANCE PROGRAMME - CURRENT 24M0 BASE CHECK INTERVAL

Calendar Calendar Calendar Calendar CalendarCalendar Approx Approx Base tasks tasks tasks tasks tasks

Base interval FH FC check applicable applicable applicable applicable applicableCheck - months interval interval groups to all A380 per to to per eng

mod status A380-841/842 A380-861 mod status

1st or C1 24 9,000-11,000 1,100-1,200 24MO 105 15 20 11 5

2nd or C2 48 18,000-22,000 2,200-2,400 24MO + 48MO 156 19 29 20 5

3rd or C3 72 27,000-33,000 3,300-3,600 24MO + 72MO 348 50 25 22 5

4th or C4 96 36,000-44,000 4,400-4,800 24MO + 48MO 161 19 30 21 5

+ 96MO

5th or C5 120 45,000-55,000 5,500-6,000 24 MO 106 15 20 11 5

6th or C8 144 54,000-66,000 6,600-7,200 24MO + 48MO 606 62 39 38 5

+ 72MO + 144MO

A380 MAINTENANCE PROGRAMME - REMAINING GROUPING OF ‘A’ CHECK FH/FC TASKS, AND VENDOR OR ‘NOTE’ TASKS

Calendar Task FH Task FC Applicable Applicable Applicable Applicable Applicableinterval interval interval to all per to to per eng

A380-800 mod status A380-841/842 A380-861 mod status

A checks 24 9,000FH And/Or 1,100FC 143 4 1 1

FH/FC OOP tasks

(within first base

check cycle of 12

years) 144 9,000FH-

66,000FH And/Or 1,100-7,200FC 530 26 39 36

FH/FC OOP tasks

(beyond first base

check cycle of 12

years 144 66,000FH And/Or 7,200FC 214

VR or ‘Note’ Various Various Various 42 12 8 5



aircraft’ restoration at144MO/12,700FC. For samplingpurposes, gears from different climateregions are being removed at an earlierinterval for initial inspections.

“We have begun a controlledsampling programme of the landing gearsat the request of authorities,” explainsSalles-Parfouby. “The first MSN landinggear has been inspected with nosignificant findings to report that couldamend the current proposed interval of144MO/12,700FC. The second gear forsampling was removed from anotherMSN in March 2018, and was in verygood condition, and another is due inAugust 2018. With no significantfindings, that part of the aircraft isbehaving as predicted.”

Deep access requirements for cabinand freight bays will be driven primarilyby the structural section 72MO and144MO task groupings.

For 72MO calendar-driveninspections there are 132 tasks: 106 applyto all aircraft, five to the A380-841/842,11 to the A380-860, and 10 to the A380-800 per mod status. Additional taskgroupings are two tasks at72MO/3,800FC/28,000FH, and one taskat 72MO/6,300FC.

Access for the 72MO inspectionsincludes, for example, removal of: wheelsand brakes; ballast weights and insulationat specific locations; lavatories andgalleys; and interior ceiling and sidewalls.Engines and pylons also have heavyaccess requirements.

For the 144MO calendar-driveninspections there are 86 tasks: 73 applyto all aircraft, three to A380-841/842,five to the A380-861, and five to theA380-800 per mod status. Additionaltask groupings at the interval of 144MO

are 144MO/11,700FC /86,800FH withone task, and144MO/3,800FC/28,000FH with two.

The 144MO deeper accessrequirements include gear retract actuatorremoval, insulation displacement forinterior inspections, further floor paneland crew rest compartment removals,flight controls and wing accessrequirements, and removal of windshieldretainers from the flightdeck.

The 144MO threshold 72MO repeatinterval grouping has 23 tasks: 21 applyto all aircraft, and two to the A380-800per mod status. These tasks will impactthe third 6YE check at aircraft age of 18due to the 72MO repeat interval. Theserequire detailed inspections of thefuselage internal structure at specificlocations including passenger cabin andfreight bays.

Engine removal for structuralinspections can be referenced in thedescription of the MPD task or in thepreparation column of the XL version ofthe MPD, and description column of thePDF MPD. An example of a ‘with engineremoved’ inspection is the special detailedinspection using high frequency eddycurrent (HFEC) of the rear engine mountassembly on a Trent engine. MPDpreparation MH for the task is listed as35.40MH.

For A check task groupings, 14structures tasks will most likely fall duebefore and between C checks. The largestquantity grouping is the 200FC group,which comprises four tasks.

Zonal The Revision 13 zonal section of the

MPD contains the smallest quantity ofinspection tasks with 191 entries, all with

only calendar intervals. Of the tasks, 156apply to all A380-800s, 14 to the A380-841/842, 14 to the A380-861, and sevento the A380-800 main- and upper-deckutility areas if galley and lavatories areinstalled.

Inspections contained in the sectionare allocated task code GVI and skillcodes AF and EN. The MRBR is thesource document for all tasks. Asreferenced by the title of the section, theinspection requirements apply to zones ofthe aircraft to check for security ofinstallations, general condition, accidentaldamage, and accumulation of anycombustible materials covered by theenhanced zonal analysis procedure(EZAP). EZAP inspections are used toidentify maintenance and inspection tasksthat minimise accumulation ofcombustible materials and detect EWIScomponent defects.

In the 24MO check cycle, zonalsection tasks fit into 10 differentparameter groupings, using 100%interval only (no threshold listings). Theinterval groupings are 3MO, 6MO,12MO, 18MO, 24MO, 36MO, 48MO,72MO, 96MO and 144MO. Tasks thatwere originally under a 1.5MO groupinghave been escalated to both 3MO and6MO.

The four interval groupings that falldue consistently between C checks willform part of the line maintenancepackages. These are six tasks at 3MO, 12at 6MO, four at 12MO, and one at 18MO. These tasks only have minor panelsand door opening requirements, as wellas flight control positioning. Anothersmall grouping that sits occasionallyoutside of the 24MO C check grouping isthe 36MO tasks, of which there are eight.These inspections require specific wingaccess panels removals and flaps/slapextended, and will most often be slottedinto the C checks.

The remaining 160 tasks fall into fivegroupings, all in line with calendar Ccheck intervals in multiples of 24MO.

There are 38 tasks for the in-servicefleet at 24MO: 34 apply to all aircraft,four to the A380-841/842, and four tothe A380-861. These tasks cover externalinspections of the lower third of thefuselage, wing and body gear bays, aftcabin and rear fuselage compartments,empennage and wing inspections. A largequantity of wing, flight control andengine panels requires removal.

The 14th revision of the A380’s MPD has seen achange in its base check programme from acycle of six to four base checks. Two structuralinspections are performed at six and 12-yearintervals.

There are another 29 tasks at 48MOintervals: 15 apply to all, seven to theA380-841/842 and seven to the A380-861. These cover deeper accessrequirements, including access gained forinternal cockpit, avionics compartmentand pylon inspections. Engine inspectionsare listed only once in the MPD if theinspection applies to all four engines. Thefour engine zones listed against the MPDwill confirm if inspections apply to all. Alarge percentage of these tasks have beenescalated to 72MO in Revision 14 of theMPD.

There are 38 tasks listed at a 72MOinterval: 31 apply to all aircraft, andseven to the location of galleys andlavatories. Twenty-eight of theseinspections require access to specific areasof cabin and cargo compartmentequipment, furnishings, and floor panelremovals.

The 96MO task grouping has onlyfour tasks: two apply to all aircraft; oneto the A380-841/842; and one to theA380-861. These tasks have wing, pylonand body fairing access requirements.

There are 47 144MO tasks, of which45 apply to all aircraft; one to the A380-841/842; and one to the A380-861.

Like the 72MO grouping, there areextensive cabin, cargo compartment andfuel tank access requirements.

A380 base checks

Man-hours The MPD shows MH in decimal

format within each Systems, Structuresand Zonal section. In the Excel version ofthe MPD there is a labour calculator thatcollates all MPD inspection information

into one place. The MH informationsupplied is in the usual Airbus format ofTask, Prep and Access.

The Task, Prep and Access MHlistings cover aspects of inspectionrequirements: Task MH for the actualtechnical performance of the requiredMPD listing; Access MH for panelremoval/re-fit and door opening/closing;and Prep MH for specific area orcomponent preparation needed tocorrectly complete the inspection.

Preparation hours require closeattention. Details of aircraft interiorfurnishing, galley/lavatory removals,landing gear, engine, even insulationblanket removal, will be covered by thePrep MH. Large MH tasks will be foundhere.

One example of a preparationrequirement with guide MH figuressupplied is the Zonal GVI of the maindeck’s forward mid-cabin and utility area.To complete this, floor panels, insulation,lavatories and galleys, seats and sidewallpanels must be removed. Preparationareas are listed within the tasks content,and a guide of 91.82MH provided.

Panel removal requirements are listednext to each MPD task where required,along with associated MH. Appendix 6of the MPD lists all 1,340 panel numbersand doors on the aircraft with guideremoval/refit MH.

The MPD still has tasks with MHlisted as to be determined (TBD) whereAirbus is yet to list the MH requirement.Under Task, 95 inspections are listed withMH as TBD. Two are listed under Accessrequirements, and 82 under Preprequirements. Often these tasks have FCor FH intervals, and require NDTinspection or unique access.

Where N/A is quoted, MH do not

apply to the task. This is the case wherethe task MH may only apply to theworkshop environment, but MH can belisted for Access or Prep.

Routine Multiplying the OEM’s estimated MH

by a reality or conversion factor has beenan accepted method over many years todetermine actual inspection MH figuresto resource base maintenance checks. Inprevious Aircraft Commerce A380articles, (see The A380’s & 747-8’s design& maintenance requirements, AircraftCommerce, February/March 2012, page45), operators noted a conversion factorof up to 7 is being used, while experiencewas being obtained on the aircraft type.

While during the initial few basechecks this may have been the case,industry feedback has determined that atask-by-task MH evaluation is insteadtaking place. “Such a factor is of courseonly a rough guideline; we evaluate everysingle case during first accomplishment,”explains Christian Rieckborn, fleetmanager (A380) at Lufthansa Technik.

Of course, routine check figures willvary according to the internal cabinlayout of each fleet. Access MH figureswill account for a large proportion ofMH calculations. In a three-class interiorconfiguration, 16 lavatories, 17 galleymodules, and additional wet floor areaswhere bars are located, typically must beremoved on the structural checks.

Crew rest area maintenance will alsocause variation in base routine inspectionand access figures. In the MPD 18 tasksapply to crew rest areas and modules.

The airline’s own inspection cards willadd MH on top of base routinerequirements. Operators will use theMPD, Aircraft Maintenance Manual(AMM), specific national regulatoryrequirements, and their own specificrequirements to form their own AMP. ForLufthansa’s fleet, about 100 additionalpersonalised tasks are included in aircraftmaintenance programmes, of which 40%are cabin-related.

Non-Routine Non-routine (NR) ratios for base

routine figures will vary depending oncheck size, condition of the aircraft, andinclusions of any customer cards partiallyassociated with rectifying the cosmeticappearance of the aircraft and interior.



The oldest A380s in the fleet are at about 12years old, and so undergoing their first heavy12YE checks that complete the first base checkcycle. Full 12YE checks are expected to consumeabout 50,000MH for the main elements ofpreparation, access, routine inspections, anddefect rectifications.

In general, for the first base checkcycle the ratio of defects to routineinspection MH starts at 0.3:1 for the C1check. It increases throughout the checkcycle, and is expected to reach 0.7:1 to1:1 for the 12YE check. Some operatorsrepresent this ratio as a percentage.

There are 89 A380 aircraft in activeservice that are more than six years old,and so will have accomplished their firststructural check at the 6YE interval.Defect findings from the in-serviceaircraft have been reported as on parwith other aircraft types, or lower.

“Based on a 72MO check, ourexperience is that NR findings are lowerthan for other fleets,” adds Rieckborn.“Usually corrosion of the seat tracks is amajor issue, but the use of titanium tracksmeans this does not apply to Lufthansaaircraft. Many issues have been addressedby modifications prior to the layover,however, so there are no surprises.”

“The ratio of routine to NR work forthe A380 is no different to any otherAirbus aircraft,” adds a spokesperson forEtihad Airways Engineering (EAE).“With the scale of the aircraft it isimportant to hit planned inspectiontargets early. In our maintenance checkplans we have what we call a CriticalDetermination Point (CDP), which iswhere all the critical inspectionrequirements of the check are targeted to

finish. By completing these criticalinspections as early as possible, you havea better chance to obtain all the supportyou need from Airbus for partsprocurement to get the aircraft backtogether in time.”

Check totals Some tasks in each maintenance check

will include clearing inspections ahead tominimise maintenance ground timebetween checks.

An example of this is a base check at24MO that may include both 18MO and24MO calendar tasks, tasks between9,000FH and 19,000FH, and tasks due at1,200-2,400FC. Using an optimisedcheck format, some FH and FC tasks maybe moved to small line checks to gain fullutilisation of the inspection parameter. Inan FH- and FC-optimised maintenanceprogramme, such as the A380’s, few basechecks will be the same.

Since the A380 entered service, Airbushas collected in-service MPD MH datafrom various operators to use as guideestimates for checks. For the routineMPD tasks only including access andpreparation, this is as follows: C1/24MOcheck is 1,500MH, the C2/48MO checkis 2,100MH, and the 6YE check (whichcan be referred to as the C3 or 72MOcheck), is up to 16,000MH.

Industry feedback for the base routinewith adjusted MPD MH that includesaccess and preparation MH, customer-specific tasks and aircraft handling is asfollows: C1/24MO check is 5,000-6,000MH; the C2/48MO check is 7,000-8,000MH; and the 6YE check (oftenreferred to as a C3 or 72MO check) is25,000-27,000MH. The large rise in the6YE figures includes the overhaul of thecabin furnishings and seats.

Using an escalating NR ratio for thebase routine, preparation and access MHfigures supplied by the airlines, the checktotal at 24MO, the labour required is6,500-7,800MH. This is using 0.3 defectMH for every routine inspection MH.

The C2 check total at 48MO is9,100-10,400MH, using a defect ratio of0.3MH per routine MH. The 6YE, oftenreferred to as a C3 or 72MO check, hasan NR guide ratio of 0.4:1, with a labourrequirement of 35,000-37,800MH.

For a more detailed look at the C2 at48MO, a routine figure across all tradeswith the MPD-factored and customer-specific cards included is 5,000MH, with1,300MH for access and preparation,and another 1,000MH for groundhandling/technical cleaning/finalfunctions/de-fuelling/planning andengineering support. This equates to aguide check figure of 7,300MH. When a0.3:1 defect ratio is applied to the base



inspection and access figure, a further1,890MH will be required, taking thesub-total for these elements of the checkto 9,190MH. Major aircraftmodifications or interior work andrefurbishment, and component changeswill require additional labour.

For a more detailed look at the C3 at72MO, a routine figure across all tradeswith the MPD-factored and customer-specific cards included is 17,000MH,access and preparation is 6,000MH, andground handling/technical cleaning/finalfunctions/de-fuelling/planning andengineering support add another1,500MH. This equates to a sub-total of24,500MH. When a 0.4:1 defect ratio isapplied to the base inspection and accessfigure, another 9,200MH will be needed,taking the sub-total to 33,700MH. Aswith the C2 check, major modificationsor interior configuration work, andcomponent changes will all be additional.The same applies to any stripping andpainting that might be included in thecheck, or performed later.

For guide costings, a C2 check with asub-total of 9,190MH for the mainelements at a labour rate of $60 per MHand a further budget of $12 per MH forconsumable materials would total about$662,000.

A C3 with a sub-total of 33,700MHat a labour rate of $60 per MH and $12per MH for consumable materials, aguide C2 check would be $2.43 million.

What impacts the 6YE check MHmore is inclusion of a cabinrefreshment/overhaul request. This willbe the same for the 12YE checks.

Base check downtimes are 17 days forthe 24MO, 22 days for the 48MO, and47-53 days for the 72MO check.

Downtimes are affected by the

addition of modification work, includingAD and SB releases to the work packs.For example, the wing rib modificationcould be carried out over differentmaintenance inputs, but when carriedover to the closest C check an extra22,000-25,000MH is needed to completethe full AD.

“Several fatigue-test-related structuralADs (flap-track fairings, wing tips,passenger doors) have to be performed,but most of the modification on theLufthansa fleet was already carried outduring the 72MO check,” saysRieckborn. “The situation might varyamong fleet leader aircraft depending onkit availability.”

Resourcing Hangar logistics and manpower

resource planning is always an importantbehind-the-scenes activity before anylarge maintenance input, especially forheavy checks on newer, larger aircraft.

A380 heavy structural check resourceplanning can follow the patterns ofsimilar-sized aircraft which have the sameengine and landing gear configurations.Where it differs is on the size of the cabin,which stretches across two full decks.

“Handling the A380 cabin requires awell-staged double cabin team,” explainsRay Kazmierczak, director at RFKConsulting. “Stripping out the aircraftinterior should take no longer than anyother aircraft if the staffing is correct. Fora 6YE input it is possible to remove allthe cabin equipment, including seats,galley and lavatory modules, and floors,in three or four days with a cabin team of50 personnel. Initially the MH needed todo this can be based on similar-sizecabins, but can be scaled up as necessary.

The same methodology will be used onthe 12YE checks, as well as in-serviceexperience gained on the type.”

“At Etihad Airways Engineering(EAE) we start preparing for the checksix to seven weeks before the input byevaluating the work scope to create acheck plan,” adds an EAE spokesperson.“The check plan will include the day-to-day inspection listing and requiredmanpower allocation. With manpowerplanning, we split the trades, forexample, into cabin, avionics, orstructures. These are then allocated to theinspection requirement of the check plan.Night coverage will also be used,depending on the inspection type, tospread out the inspection loads in criticalor confined space areas. This is not verydifferent from any other check apart fromthe amount of labour required. It is alabour-intensive aircraft, which in turnneeds some resourcing flexibility. If thecheck progress lags behind, you need aclear link to resource allocation to seehow to recover the time.

“Additionally while performing A380maintenance, what needs to beconsidered, especially on the heavierchecks, is not just the MH required, butsecuring the essential support neededfrom the OEM,” further explains theEAE spokesperson. “EAE is part of theAirbus Alliance, in which Airbusrecommends the MRO facility as anA380 Center of Excellence. Subsequentengineering and materials support fromthe OEM plays a key role in assisting thedelivery of the aircraft on time.”

Another consideration when carryingout A380 maintenance is the hangar floorspace commanded during the input.Additional planning is needed to includeenough workable area for the largequantity of cabin equipment to beinspected, overhauled/repaired, andstored pending re-installation.

“To carry out A380 maintenanceefficiently, the infrastructure needs to becorrect. A big part of that infrastructureis interior workshop capabilities,” saysKazmierczak. “At 6YE check intervalsmost operators are removing andrefurbishing/upgrading the completecabin. I see this being the same for the12YE checks. This requires an interiorshop of 3,000 square metres per aircraftto support the removed cabin equipment.This shop is ideally located close to theaircraft for efficient access. The aim is tostart refitting the cabin after two weeks.”



Direct labour inputs for the 6YE check are about25,000-27,000MH. After initial experience withthe first checks, the non-routine ratio for the 6YEcheck is about 0.4, thereby adding a further10,000-11,000MH.

The importance of cabin interiorsupport is also noted by EAE. “On the6YE and 12YE inputs you need space,labour, and importantly you need back-shop support,” adds the EAEspokesperson. “We have these threerequirements. In parallel to the MRO,EAE has the essential expertise to processthe cabins through the back shops. Thecabin has become our speciality.”

An additional commercial complexityis the aircraft’s large hangar footprint.

“If you are completing A380maintenance, you have to be doing wellover 1,000MH per day to cover thehangar space’s potential earnings,” saysKazmierczak. “This puts pressure onother departments, such as engineeringand logistics, planning and purchasing,and any other support service needed forthat particular input. If the same hangarcould take four narrowbody aircraftachieving 500MH a day, then it could begenerating 2,000MH a day. These are allfactors to consider and price for.”

12YE/144MO check The first 12YE checks are now under

way. Experience from the 6YE structuralchecks will be a huge factor in estimatingMH required for the 12YE check.Currently end-of-lease aircraft are thefirst to have the scheduled check. Whileshop-floor data collection will be ofinterest to other airlines planning for thechecks, any additional requirements,including cabin configuration changesand general cosmetic work, will disturbthe potential flow of the scheduledmaintenance data for collection purposes.

Airbus is in constant contact withcustomers leading up to the checks.

“For everything around thepreparation of the check, Airbus is inconstant communication with theoperator for support needs,” explainsSalles-Parfouby. “This includes theavailability of Ground SupportEquipment (GSE), carrying out repair andrisk assessments, and to support any taskoptimisation the operator is looking foror would like to proceed with.”

“We estimate that the aircraft willrequire 50,000MH for the technicalinspection tasks and defect rectification,”explains Stegerer. “This figure excludesany preparation, access, or cabinreconfiguration work, or repainting thatmay be needed. So more than 50,000MHwill be needed in an airline operation

where many additional cosmetic tasks areincluded at the same time.”

A 12YE check figure could be well inexcess of 75,000MH when includinglanding gear changes, cabin configurationand decor changes, reliability programmecomponent changes, aircraft re-painting,and end-of-lease or aircraft transfer workpackages to a new operator if required.

Beyond 12YE check As expected, a large number of task

thresholds fall beyond the 12YE checkcycle within the structural inspectionprogramme. Utilisation of each aircraftwill affect when these intervals arereached in terms of calendar time.

For example, there are 37 differentthresholds for 39 different tasks from8,500FC to 8,900FC, and which have a62,600FH to 66,000FH back stop. Thehigher FC aircraft utilisation will hit thisat 13-14 years, while the higher FHutilisation aircraft will hit this at 12-13years. For these aircraft the tasks willmost likely be cleared on the 12YE check.

For lower FC utilisation aircraft, thesame tasks will fall due at 19-20 years,while the lower FH utilisation aircraftwill hit this at 14-15 years. For theseaircraft the inspection tasks will either beincluded on a case-by-case basis, orbrought forward to the 12YE check.

Another 211 tasks fall due from9,000FC to 18,700FC, and 66,600FH to136,000FH. These will come due at 15-30 years of age in accordance with mostairlines’ rates of utilisation. Most of theseare NDT inspections, including X-ray.

Many of the tasks have a reducedrepeat interval that in some cases will falldue again within the same base checkcycle. Aircraft utilisation will affect the

calendar time these tasks fall due. The highest FC structures task

threshold is 18,700FC, with a 9,000FCrepeat interval for an NDT inspection ofthe pin between NLG hinge and NLGbay 1. Task and preparation MH arecurrently listed as TBD.

The highest FH threshold is136,000FH with a 29,000FH repeatinterval for a detailed inspection of thefuselage internal structure vertical beamsof the NLG bay side panel. Task MH arelisted as TBD.

For the systems section only threetasks of a high threshold are above the12YE check cycle, two of which are72,000FH interval tasks for a visualcheck of the cabin air distribution mixerunit and a detailed inspection of the stairattachment point. The other is an80,000FH task for removal of hat rackshutoff valves for in-shop functionalchecks of the passenger oxygen system.This will come due at 14-18 years.

Within the Zonal section of the MPDall inspection tasks are contained withinthe 12YE cycle.

Summary The move towards a 36MO base

check cycle is a big development for theA380 maintenance programme and willhave a large impact on reducingmaintenance costs. Deletion of twochecks from a base check cycle in oneMPD revision is rare. Given the A380’scurrent push through the 12YE heavycheck milestone, its MPD is at aninteresting point in the lifecycle.



In addition to aircraft preparation, access,routine inspections and defect rectifications;maintenance planners also have to considerinterior cleaning and refurbishment, componentchanges, modifications, and strip and paint atadditional elements of heavy checks.

To download 100s of articles like this, visit:

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AIRCRAFT COMMERCE ISSUE NO. 1 • SEPTEMBER/OCTOBER 1998


a380 mpd & base maintenance analysis...the oldest a380 aircraft are now approaching the end of...

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