2. AUGUST2013AUSTRALIANAVIATION 3
nitiatives to improve airspace and
airport capacity at Australia’s
major airports are fostering
unprecedented cross-industry
collaboration.
Four initiatives are underway
at Perth, Brisbane, Melbourne
and Sydney airports to optimise
airport movement capacity and
operations in surrounding airspace.
These initiatives comprise an airport-
directed slot management system, the
Airspace Capacity Enhancement (ACE)
program, Metron Flow Control and
daily performance reporting to achieve
continuous improvement.
In the past, highly tactical methods
of providing airport infrastructure and
air traffic services dominated thinking.
Airlines had discretion over when they
preferred to operate, with airports and
Airservices providing infrastructure
and services to meet this demand as
best they could. Aircraft delays in the
air and on the ground were accepted as
a natural consequence and managed by
operational staff.
However, the sharp increase in
aircraft movements arising from
increased airline competition and
large numbers of fly-in/fly-out (FIFO)
movements has resulted in extreme
pressure on airport infrastructure and
the air traffic management (ATM)
system at peak periods. Solutions
that involve providing more airport
infrastructure and new ATM systems
are both extremely costly and involve
long lead times to plan, procure
and bring into service. When user
demand exceeds the capacity of airport
infrastructure and the ATM system,
aircraft generally receive airborne or
ground delays. These delays increase
airline operating costs.
Over time it had been largely
the responsibility of Airservices to
manage movement capacity issues
with airlines. Airports typically had
a limited focus undertaking master
planning, addressing aircraft ground
congestion and managing the noise
issues with local communities arising
from increased air traffic. In the past 18
months new strategic initiatives have
been introduced by airport companies
and Airservices to better meet the
demands of increased traffic levels.
This has seen airports become an
integral element in a national solution,
implemented at a local level, to address
these system capacity problems.
Airports are beginning to appoint
senior operations managers who have a
background in ATM capacity planning.
Metron Flow Control was
implemented for Sydney and Perth in
March 2012 and became operational at
Brisbane in December 2012. It is a pre-
tactical method that seeks to balance
traffic demand with the capacity of the
ATM system.
Next-day aircraft schedules and
weather forecasts are uploaded into
the Metron system. This information is
sourced from airport slot management
schemes. Software algorithms process
weather forecast information with
predicted flight profiles and aircraft
operating parameters to establish the
arrival and departure rate for the day.
Metron then integrates the proposed
flight schedules with the predicted
arrival and departure rate. The outcome
sees departing aircraft assigned a
departure time, while arriving aircraft
are given a target arrival time. In the
case of more than one aircraft seeking
the same time, Metron randomly
chooses the order and places other
aircraft into slots as close as possible to
their requested time.
Meanwhile, enhancements are being
undertaken with regular scheduled
airlines and the meteorological service
to introduce more accurate weather
parameters into the calculation of the
arrival and departure rate.
Metron is primarily an ATM tool
managed centrally from Airservices
National Operations Centre (NOC)
in Canberra. It performs well when
used to balance capacity and demand
in the ATM environment, but it is
not designed to manage the strategic
process of assigning airport slots to
airline flight schedules. Nor is it suited
to applying local rules at different
airports. When this has occurred,
some user resistance to Metron
implementation and non-compliance to
procedures has resulted.
A cornerstone initiative for Perth
and Brisbane airports has been the
introduction of a slot management
scheme. It is a strategic tool initiated
when an airline applies to introduce
a scheduled service at an airport.
These slot management schemes are
the first gateway in regulating aircraft
operations at an airport and for the
ATM system.
Both Perth and Brisbane have slot
management schemes based on IATA
Worldwide Slot Guidelines with local
rules defined for how slots are assigned.
While both airports set the rules for
how the schemes will operate and
procedures to monitor performance,
day-to-day management is undertaken
by Airport Coordination Australia.
Brisbane
For Brisbane Airport, the slot
management program is termed
the Runway Demand Management
Scheme (RDMS). The RDMS was
first implemented in October 2012 in
response to increasing demand and
a request from Airservices that the
airport implement a slot management
system before the introduction of
Metron Flow Control. Lessons learned
from the Metron implementation at
Perth identified the need for an airport
solution to regulate traffic demand.
In the first months of operation
Brisbane had some teething troubles
in accurately defining the appropriate
aircraft movement metrics that could
be achieved. Unlike Perth, Brisbane
did not have data about actual arrival
and departure rates achievable with the
operation of Metron procedures.
Mark Willey, head of airport
development at Brisbane Airport
Corporation (BAC) explained: “At the
outset of RDMS, movement metrics
were defined that were a stretch
target based on the demand that was
presenting at peak periods. A capacity
study undertaken by UK ATM provider
NATS suggested a marginal increase in
the arrival rates could be achieved.
“The RDMS arrival and departure
rates for runway 01/19 had been based
on an assumption of good weather
conditions, which provides for 27
arrivals per hour and a maximum
of 50 total aircraft movements. This
assumption of a high percentage of
good weather operations was overly
optimistic for RDMS Season 1, with
extended periods of poor conditions
being experienced exacerbated by the
closure of the crossing runway for early
works associated with the new parallel
runway,” Willey said.
“In comparison, the arrival rate
metric for Metron, which became
operational at Brisbane two months
LessonslearnedfromtheMetron
implementationatPerthidentifiedthe
needforanairportsolutiontoregulate
trafficdemand.
3. 4 AUSTRALIANAVIATION AUGUST2013
Intheslot
after RDMS, is about 23 per hour,
which is four less than RDMS. This
imbalance was addressed in our first
review of the system and we are now
de-peaking the arrival rate in high
demand periods to an arrival rate
below 27. With operations now able to
take place on the crossing runway, the
Metron rate in daylight hours is up to
28 arrivals per hour.”
Two other issues have presented
some complexity. Non-scheduled
services such as the Royal Flying
Doctor Service (RFDS) or business jets
are not incorporated into the RDMS
seasonal schedule and often seek to
operate with less than 24 hours notice.
RFDS operations can account for
up to 30 movements on some days.
These operations need to secure an
RDMS slot and a space in Metron from
Airservices’ NOC and are subject to
gaps being available in the aircraft
movement schedule.
Airlines wishing to secure FIFO
contracts need to confirm their ability
to operate at specific times as part of
the tender and contract negotiation
process with resources companies.
However, these times are not able to be
confirmed without a formal schedule
request. This presents difficulty for
FIFO airlines entering into contracts
with clients, which often stipulate
performance compliance to assigned
departure and arrival times.
A review of the efficacy of the
RDMS is planned to occur every six
months aligned with international
scheduling seasons, with the first
two reviews having taken place in
February and April 2013. Taking into
consideration the need to provide gaps
in the schedule for non-scheduled
services, some contraction in the hourly
movement rate is desirable.
BAC is mindful of the lead-time to
reduce movement rate metrics and the
need to maintain ongoing slot times for
scheduled services. Adoption of a more
conservative rate requires a number of
months’ notice along with negotiation
and consultation before reduced
slot availability can realistically be
incorporated into airlines’ schedule
planning. It is expected an increase in
the hourly movement rate in line with
the optimal capacity will be achieved
through the implementation of ACE
airspace enhancement initiatives.
Perth
The Slot Co-ordination System (SCS) at
Perth Airport has been operational since
March 31 this year, one year after the
implementation of Metron. From having
a significant body of performance data,
it has been a straightforward process
to align the movement rates of both
systems.
Peter Cock, executive general
manager, operations & customer
experience at Perth Airport said:
“We started discussions early
with Airservices to determine the
appropriate movement metric well in
advance of the SCS implementation
date. The intention was to agree a
figure that could be incorporated into
both SCS and Metron. We intentionally
defined a challenging movement rate
for the system to achieve.”
One of the challenges Perth Airport
had to address was the development of
local rules for SCS that addressed the
operational needs of FIFO airlines and
the resources sector. Cock describes the
allocation process for these users.
“In setting local rules we adopted
principles that included issuing SCS
slots up to its maximum capacity, not
holding spare capacity and providing
grandfather rights to a slot occupied by
a FIFO airline in the same manner as a
RPT airline. Although a slot is assigned
to a FIFO airline it is also linked to a
specific route. This enables a slot to be
assigned to a different airline should
a contract for FIFO services change,”
Cock said.
“We also need to guard against
an event where one FIFO airline
assumes a contract from another but
replaces a large aircraft with two of
smaller capacity. For airlines seeking
to commence a new service their time
of operation remains subject to an
available slot.”
These local rules also address
how multiple bids for a slot in peak
periods are prioritised. Cock explained:
“Assignment of a slot in peak periods
takes account of the operational
circumstances of the airlines
concerned. For example, a FIFO airline
operating to and from an airport with
limited infrastructure would be given a
priority for a slot that enabled daytime
operations.”
Having the slot allocation method
taking account of local circumstances
has resulted in reduced delays and
improved user compliance, compared
to the previous Metron-only system.
Metron seemed to suffer a backlash
from local operators who believed that
arriving intrastate operations were
disadvantaged due to operations only
within 800nm of Perth Airport being
subject to flow control.
In comparison, aircraft arriving
from interstate are not subject to
these controls. At times FIFO airlines
would choose to get airborne from a
rural airport in contravention of their
assigned time to avoid weather or
impending darkness when adequate
lighting was not available. An airport
slot scheme applies equally to all
airlines irrespective of their point of
origin or destination.
Cock reported initial indications
point to approximately a 60 per cent
reduction in arrival and a 70 per cent
reduction in departure delays with
the introduction of SCS. Previously,
AFIFOairlineoperatingtoandfrom
anairportwithlimitedinfrastructure
wouldbegivenapriorityforaslot
thatenableddaytimeoperations.
petercock-perthairport
Terminalairtrafficmanagement
hastocontendwithmixesof
aircrafttypes,andinthecaseof
SydneyAirportprotectregional
airaccess.seth jaworski
4. AUGUST2013AUSTRALIANAVIATION 5
airlines could experience departure
delays of up to 90 minutes. This
delay has now reduced to an average
maximum of 15 minutes.
Optimisation
ACE is a multi-faceted initiative aimed
at achieving optimal runway capacity at
Australia’s four major airports. It seeks
to maximise the aircraft movement rate
at Perth, Brisbane and Melbourne.
At Sydney, the goal is to attain the
maximum movement cap of 80 per
hour. ACE seeks to achieve capacity
enhancements by removing inherent
inefficiencies that presently exist
within various elements of the system.
ACE is led by Airservices, but has
active involvement from airports and
representatives from airlines and non-
scheduled users. It is jointly funded by
Airservices and the airports.
The first step in the ACE program
was the completion of an operational
performance and capacity assessment
for each of the airports. NATS
Consultancy, an offshoot of the United
Kingdom’s air navigation service
provider, was chosen to provide new
thinking to resolve capacity issues and
for their experience at Gatwick Airport,
which is commonly considered to be
one of the most highly optimised single
runway operations globally.
Airservices’ executive general
were developed from evaluating
current operations and benchmarking
performance with two international
single runway airports. The end result
was a target movement capacity
developed for each airport that could
be achieved with improvements in the
operational efficiency of a number of
areas.
Initiatives that provided the most
significant opportunity to increase
runway capacity were reducing spacing
between arriving flights, the adoption
of standard arrival speeds and reduced
runway occupancy times. For Brisbane,
23 capacity initiatives have been
identified. At each airport specific
working groups are formed to address
the major items.
Of these, the adoption of standard
arrival speeds is probably the key
element. Standard arrival speeds
provide predictability to air traffic
controllers who can then have the
confidence to reduce the spacing
between arriving aircraft. It also
enables gaps between arriving aircraft
to be more effectively planned to
enable departures to take place.
Rick Davies, the RFDS’s head of
flying operations and a member of the
Brisbane ACE Steering Committee
said: “A lot of work has taken place
in establishing the appropriate arrival
speeds. The issue is complicated due
Weare
exploring
otherinfra-
structure
optionsto
increase
capacity.
MARKWILLEY–BRISBANEAIRPORT
manager ATC Jason Harfield explained:
“The industry is faced with meeting
increasing traffic levels without new
airport infrastructure becoming
available until at least the end of this
decade. To meet these demands we
need to extract latent capacity within
the existing operations undertaken by
airlines, airports and Airservices.
“NATS undertook studies at each
of the four airports in early 2012.
Their brief was to identify initiatives
to maximise the available capacity of
existing runways. Initiatives to release
latent capacity require all industry
players to work together. To implement
the host of changes, a strategy and
action plan for each airport has been
agreed with industry stakeholders.
For each airport an ACE steering
committee and working groups have
been formed to undertake initiatives as
well as provide oversight. Membership
of the steering committees includes
participants from the airport concerned,
scheduled and non-scheduled users and
Airservices,” Hatfield said.
The NATS studies involved
determining the maximum runway
capacity and identifying measures
needed to increase current performance
to achieve this maximum capacity.
The process involved a seven-day site
visit to review traffic data and observe
operations. Performance metrics
Collaborationbetweenairlines,
airportsandAirservicesiskey
toimprovingcapacity.
brenden scott
5. 6 AUSTRALIANAVIATION AUGUST2013
Intheslot
to the variety of aircraft types and
variations in how different airlines
operate the same aircraft. For Brisbane,
arrival speeds are defined at three
mandatory ‘turnstiles’. Aircraft unable
to achieve these speeds are required
to make greatest speed for as long
as possible.” These speed control
initiatives are detailed for each airport
in ERSA.
Adoption of standard arrival
speeds and the need to reduce runway
occupancy times have required
considerable efforts in crew education.
Each airline is encouraged to train
flightcrews on standard arrival speed
procedures and practices to reduce
runway occupancy times. In support
of airline training, Airservices has
prepared information brochures for
users at each airport that include
suggestions for flightcrews to adopt as
they prepare for departure and preferred
runway exit points for arriving aircraft.
At Brisbane, improved utilisation of
cross-runway 14/32 would also result
in an increase in capacity. Willey said:
“The cross-runway can be used by
Code C jet aircraft as well as turboprop
aircraft. Analysis suggests that up
to 15 per cent of peak-hour capacity
could be undertaken on this runway.
However, following a safety incident in
2010 the regulatory agencies imposed
operational restrictions that reduced
usage to around five per cent, lower
after dark.” An ACE working group is
addressing how usage of 14/32 could
safely increase.
Considering other possible airport
infrastructure enhancements, Willey
noted: “NATS’ analysis indicated
runway 01/19 is already operating at
near maximum capacity. Although
Brisbane has two sets of rapid-exit
taxiways, we are exploring other
infrastructure options to increase
capacity. These options will be
modelled to determine the benefits
from an investment in additional
infrastructure.”
From an air traffic control
perspective, there is work planned to
redesign terminal airspace and revise
procedures with the nearby RAAF
Amberley.
Airservices is evaluating a ‘Brisbane
South Sector’ to improve operations in
terminal airspace including ensuring
aircraft are stacked at correct intervals
on final approach. This involves
achieving minimum spacing for a
stream of arriving aircraft or ensuring a
gap is provided for departing aircraft.
At Perth, evaluation is being
undertaken to analyse a potential
investment in additional rapid-exit
taxiways (RETS).
“Perth is assessing the benefits
that may arise from constructing
additional RETS,” Cock said, adding:
“ACE initiatives have resulted in
more predictable aircraft operating
characteristics. It enables more accurate
traffic simulations to be undertaken
to locate the optimal position of these
RETS. SCS also supports this evaluation
by providing sound traffic data to base
future traffic projections on.”
The successful implementation of
ACE initiatives brings a number of
benefits that Airservices said could
result in capacity increases of between
five and 15 per cent without major
investments in airport infrastructure.
ACE initiatives establish consistent
aircraft operating characteristics
to provide greater accuracy in
assigning arrival and departure rates
used in Metron and the airport slot
management schemes. NATS is
scheduled to return in early 2014 to
undertake a program review.
A critical element of these
capacity enhancement programs is
the introduction of daily reporting of
system performance at each airport.
Harfield emphasised the importance of
this initiative.
“Airservices has appointed a senior
manager to review system performance
and coordinate initiatives with airports
and airlines as well as the air traffic
control operation. The process involves
gathering data on performance
metrics daily and reporting results to
stakeholders.”
Rick Davies added insight from
a pilot perspective: “Airservices is
recording and providing accurate detail
to airlines. An airline could identify
the specific flight that has not complied
with required procedures. Having
operators receive performance metrics
and levels of compliance will inevitably
drive further operational improvement.”
Perth and Brisbane airports are
also collecting their own performance
metrics daily from their slot
management schemes. Both airports
are assigning additional staff to this
measurement and reporting process,
with the data shared with Airservices
and airlines, while compliance issues
are addressed with the operator
concerned.
One of the most significant benefits
from the initiatives to better balance
aircraft demand with the system
capacity has been the manner in which
airports, Airservices and airlines have
collaborated. Harfield provided an
Airservices perspective.
“A significant paradigm shift has
taken place in how the various industry
groups have worked together. Each has
a better understanding of the issues,
how the problems can be resolved
and their role in solving capacity
problems.”
Slotsforinternationalservices
needtotakeintoaccount
manyfactorsincludingslot
availabilityatotherairports.
seth jaworski
