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Nevertheless, a decade’s operations have seen the A380’s op-
erational reliability — the rate of aircraft-related technical delays
(of 15 minutes or less) — constantly improving. Compared with
an early-2017 overall global rate of 98.9 percent, Airbus says that
575-tonnes maximum take-off weight A380 variants — machines
delivered in the past four years — have scored “above 99 percent”.
The A380 has a 19,000 flight-cycle (FC)/14,0000 flight-hours (FH)
design service goal, largely driven by maintenance targets that
were a major influence in selection of initial inspection thresholds
and repeat intervals for structural items. Maintenance objectives
were also a consideration in its choice of advanced materials for
the plane’s construction.
Airbus chose glassfibre-laminate reinforced material (Glare), which
offers significant weight savings over traditional light alloys. It also
provides “very good” fatigue- and damage-resistant characteristics.
“ We have been continuously working to improve operations, facili-
tate maintenance, and increase profitability of the aircraft, in particu-
lar with an optimised cabin space,” according to A380 programme
head Alain Flourens in a November 2016 Airbus technical report.
“ We are offering improved cabin layouts so [that] airlines can opti-
mise revenues. Increased cabin flexibility also meets market needs.”
At the outset of the programme, A380 maintenance and reliability
targets became detailed requirements, agreed during feasibility
and concept-design phases with Airbus Customer Services and
Marketing departments (and augmented by input through airline
“workshops” and customer focus groups). The essential philosophy
combined “on-condition” maintenance, based on traditional checks
for installations and structures with systems-condition monitoring
that used “enhanced” on-board information and maintenance sys-
tems (OIS and OMS).
Maintenance-interval optimisation relies on having collected
scheduled and unscheduled data from various environments, in-
cluding aircraft of differing age, configuration, and utilisation. Ten
years ago, the industry adopted International MRB Policy Board
Issue Paper 44 — known simply as IP44. This “requires sufficient
in-service data and [a] sufficient number of [maintenance] task
occurrences,” says Airbus.
At the start of 2017, the “fleet-leader ” had clocked over 42,000FH
and 5,000FC, while the 207 A380s in service had logged more than
With operational data a key element, A380 maintenance optimisa-
tion covers engines, systems, and zonal-inspection work and aims
to reduce structure-inspection tasks under airworthiness-limitation
Airbus launched the optimisation programme in mid-2015, with
related maintenance-industry committee and working-group activi-
ties following in 2016. As a result, 95 percent of A380 A-check items
are now performed at (or above) 1,000FH. C -check optimisation has
followed, but the manufacturer cannot yet optimise 6YE/intermedi-
ate layover (IL) checks.
Under MRBR procedures, which set minimum maintenance re-
quirements for type-certificated aircraft (or derivatives), the A380’s
maintenance-planning document defined inspection intervals by
FC, FH, or airframe age.
For block-check maintenance in typical airline use, light A-check
tasks were initially assigned 1,000FH intervals, and heavier C checks
were given two-year (or 6,000FH) periods.
Airframe structural checks, requiring base-maintenance visits to
engineering workshops, are prescribed at 6YE/IL intervals. Accord-
ingly, before the first such inspection, there are two shop visits before
the first 6YE, rather than three as on most other types, says Airbus.
While Airbus looks forward to synchronising 6YE/IL (light struc-
tures maintenance addressing primarily corrosion and “zonal” in-
spections) and 12YE structures-maintenance tasks and landing-gear
overhauls, it cannot extend optimisation that far until the fleet has
completed more operations. “ The number of [6YE/IL] events up to
2017 does not permit [us] to demonstrate [IP44] compliance for [a
longer] interval,” says the manufacturer.
What will such structure checks and undercarriage work involve
and when will they begin? During A380 fatigue testing, Airbus
identified a few “items” and is planning related inspections. Simul-
taneously, the company is working on modifications that, when
introduced, will cancel the inspection requirement.
It hopes to be able to bring in the changes before the first A380 12YE
check in about two years’ time. Landing-gear units are continuously
being “sampled” to confirm adequacy of the 12YE overhaul target.
The A380plus study now underway demonstrates the continuous
nature of aircraft development. The manufacturer has previously
revealed, for example, future innovations that include high-slip in-
duction-motor fuel pumps expected to improve reliability and related
pump-maintenance costs by introducing “A350-like technology
having almost no electronic parts”.
Many improvements, modifications, and updates can be applied
during routine maintenance, while others may first be available as an
assembly-line fit. Some potential changes included in the A380plus
exercise have already seen the light of day at April’s specialist Air-
craft Interiors Expo cabin-equipment exhibition in Hamburg. Airbus
unveiled, for instance, a “new forward staircase” option that it could
introduce on production aircraft, although the manufacturer has not
yet decided whether it will be available for retrofit. Such options
are subject to business-case analysis covering aircraft downtime,
labour, parts-kit, and service-bulletin costs to be set against an A380
operator ’s potential return on investment, says Airbus.
A cabin-architecture change planned for early-2019 introduction
is an “aft-galley stair module” involving “a U-shaped stair and inte-
grated galleys” that would permit removal of galleys near main-deck
Door 4. Compared with the current rear staircase, Airbus says that
the module allows up to an extra 14 seats to be accommodated and
would be available in retrofit.
◀ An A380 undergoing maintenance.
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