Proceedings 2002/2003 - IRSE

66 MIGRATION TO ERTMS ON EXISTING LINES
Interoperability does not only mean that a train
should be able to be operated across borders and to
read signalling in different countries in fact.
There is also “operator interoperability” – different
train operators may run trains on the same infrastructure
even within a single country (as happens in
the UK).
And there is “supplier interoperability” – different
rolling stock may be fitted with products from
different suppliers. For example, vehicles equipped
by supplier “A” and vehicles equipped by supplier
“B” must be able to run efficiently on infrastructure
implemented by supplier “C”.
ERTMS/ETCS will bring interoperability much
more efficiently than any other solution could.
Safety
ERTMS/ETCS brings an improvement in safety,
especially in countries such as the UK where ATP
does not really exist at present.
For applications on conventional lines, from
secondary lines to complex stations and dense
areas, it will improve safety by providing ATP and,
later, cab signalling.
Capacity
There are three levels of ERTMS/ETCS equipment.
Whereas Level 1, which simply superimposes ATP
on to existing lineside signalling, does not improve
line capacity, Levels 2 onward will improve both
capacity and the global throughput of the network.
Figures from +10% to +30% in comparison with
present capacity have been either quoted or
demonstrated.
ERTMS/ETCS will improve capacity especially in
busy areas by providing smoother operation. Drivers
have a permanent reminder of the state of the
signalling and indications ahead, and can choose
when to slow down, either at the last moment or
earlier if the line ahead has not cleared. ERTMS/
ETCS also provides a much better ergonomy of
driving, especially in bad weather conditions such as
rain, snow and fog.
Level 1 does not offer any increase in line
capacity from provision of infill information in denser
areas or the approaches to them. However, in this
situation infill data can be transmitted by other
means, such as radio.
Availability
Standardisation on ERTMS/ETCS means much
less equipment than with past installations such as
Eurostar and Thalys where different ATPs were
juxtaposed for international traffic.
Less equipment and hence fewer interfaces, fewer
power supplies and other devices prone to
unreliability, fewer cables and connections all mean
dramatically improved reliability and availability, for
the signalling itself and hence for rail transport
generally.
ERTMS/ETCS also provides a range of maintenance
aids, supporting preventive maintenance
and remote diagnostics.
Cost-effectiveness
ERTMS/ETCS is more cost-effective than existing
conventional signalling solutions because it is
product-based, the same products being used by
different operators. Fewer products in the catalogue
means greater quantities to be manufactured,
lowering the costs. Fewer items to be kept for
maintenance purposes will ease everyday operation
and maintenance procedures and so reduce costs
there as well.
Less On-board Equipment
ERTMS/ETCS will, in the short or medium term,
mean that there will only be one on-board computer.
Similarly there will be only a single Driver's Man-
Machine Interface (DMI or MMI), making possible a
much simpler and more ergonomic driver’s desk
design by comparison with the six ATP systems in
Eurostar cabs and the eight in Thalys.
Less on-board equipment does not only mean
lower costs, a simpler driver’s desk and less MMIs,
but also less volume required for installing trainborne
signalling equipment – a point sure to be
much appreciated by our rolling stock colleagues.
Open Market
This was a major requirement of the European
Community from the outset The main reason for
opening the market was to reduce national influence
and privileges. Another concept was to allow any
railway to purchase from suppliers anywhere in
Europe, not only from national suppliers, and also for
any supplier to be able to bid anywhere in Europe.
To complete the main goals of ERTMS/ETCS, it
must be said that ERTMS/ETCS is in general terms
a better solution to the needs of modern railways
than any other kind of ATP. It is better adapted to
mixed traffic (ie to both freight and passenger traffic,
or to both low-density lines and the busiest stations
and junctions). It is compatible with all existing
signalling products and systems. It is independent of
any presently installed or future trackside products;
it does not for instance require use of any specific
type of track circuit. And it requires installation of
much less trackside equipment than any other type
of ATP, which results in lower installation, operation
and maintenance costs.
So ERTMS/ETCS can doubtless be said to be a
key player, if not THE key player, in improving rail
transport.
RETURN ON INVESTMENT (ROI) WITH
ERTMS/ETCS
Although the main reasons for regarding
ERTMS/ETCS as the future of European railway
signalling are interoperability for international traffic
and increased safety through provision of ATP and
cab signalling, as is often said, “Safety does not
pay”. Put another way, safety alone cannot justify
ERTMS/ETCS. So we must look elsewhere.
In seeking ways of obtaining a RoI for ERTMS/
ETCS, three potential areas have been identified:
• “standard” sources, by improving rail operation;
• areas new for signalling systems;