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might have. Whilst solving the capacity
challenge, it may have a negative effect on
environmental sustainability questions.
High-speed trains (HST) have managed
to divert some domestic traffic, but as
the report suggests, this is going to be a
focused rather than a broad-brush solution.
The extent of infrastructure investment
required to take a significant amount
of the traffic appears to be economically
unsound. Larger aircraft, in the form of
the Airbus A380, can however make a
significant difference to congestion where
the airports are able to operate them.
That said, the introduction of these larger
aircraft points to the need for all parts of
the network to prepare for the arrival of
new technology and platforms simultaneously
or risk having the additional costs
required to solve the wake vortex issue
which the A380 brought with it.
The Single European Sky and its ATM
Research programme, SESAR, represent
the other most effective way to address
these challenges, along with airport
expansion. The report shows that SESAR
at airports, together with investment to
bring each airport to the performance of
the 慴est in class? has the potential to
increase airport capacity by a significant
margin. If all the investment required is
made, it will be able to reduce unaccommodated
demand by as much as 40%.
Patrick Ky, Executive Director of the
SESAR Joint Undertaking, accepts that
the long-term-challenges present serious
obstacles and, in his words, 揝olving
them completely may be a little ambitious.?
He goes on though to reveal
how some of the mitigation concepts
being investigated, are based around
very simple ideas. For example, wake
vortex separation minima are uniformly
imposed on aircraft regardless of whether
a threat exists or not. SESAR is therefore
developing systems which will establish
the existence and extent of the threat,
based on the prevailing conditions ?
wind, temperature and pressure ?at
the airport. This will allow the distance
between aircraft to be decreased when
the threat is low and increased when it is
high.
Other airport capacity enhancement strategies
are centred on carefully managing
the traffic coming into land and preparing
to take-off. Queue management and
sequencing are not new, but Ky explains
that SESAR intends to take current
concepts, such as Collaborative Decision
Making (CDM) 揳 step further? If everybody
involved has exceptionally up-to-
Long-term solutions to long-term challenges
By 2030 it is very
likely that as many
as 19 airports in
Europe will be
operating at
full capacity.
Skyway 50 - Winter 2008 29
date and accurate data, certain tactical
steps can be taken in advance of aircraft
arrival and departures. Aircraft flying into
congested airports like Heathrow can
have their speed over the Atlantic Ocean
tailored so that instead of having to go
into a holding pattern over the airport
environs, they can seamlessly join their
landing queue without any alteration to
their routes. At the other end of the cycle,
if everybody knows exactly when aircraft
are expected, gate congestion ?in other
words aircraft hanging around waiting
for their turn to empty their passengers
into the airport ?can also be minimised.
Aircraft which are blocking the arrival of
others can leave their gate once all their
cargo and passengers have been loaded
and go off to a special parking area
where they can wait ?with their engines
switched off ?for their turn to take-off.
A more futuristic ATM concept is also
being investigated for smaller airports.
Ky reveals that SESAR intends to test
and evaluate new technology, which will
enable the remote provision of air traffic
control services for small airports. 揟his,?
he says, 搘ill result in significant economic
gains for air navigation service providers
who will be able to concentrate their staff
in a single facility whilst providing ATM
services for multiple airports.
The risks
Marsh outlines his vision of the future
for the air traffic system where a performance-
driven network operates so
smoothly that its presence is practito
pass all the necessary legislation
which supports projects like the SES
programme. Marsh pointedly explains
that legislation is a reflection of things
which are not yet happening but need
to. The second SES legislative package
was required because, although much
of the required action had been taken,
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Skyway Magazine Winter 2008(22)
