Neil Williams wrote:
Ken wrote:

Most European countries find both of them very useful.

The main thing that prompts them to use DD trains is to save money.
They tend (TGV Duplex excepted) to end up largely on short regional
trains that could easily be made longer for that reason. This even
happens in countries like Germany where low platforms mean that longer
platforms are cheaper than the UK.

Bendy buses are a different matter, and their suitability for, say,
German-style operations has a different reason behind it. In a typical
large German city, there exists an integrated public transport system
with sufficient capacity on all modes and a good distribution. Thus,
the purpose of a bus is to move people in the areas not served by rail
rapid transit of whatever type to the nearest station on such a system.
There are comparatively few bus services that penetrate the city
centre compared with London, and most of those are rather short
distance runs.

In the UK, by contrast, it is common for buses to provide a through
service from a location not served by rapid transit rail (of whatever
type) to the city centre. Outside London, this is often a competitive
service. This means longer journeys by bus than would be typically
seen in the mainland European city. This, in turn, means that people
are more likely to be bothered about wanting a seat.

The double-decker bus, therefore, is more suited to such a situation.
It means that the long-distance travellers can take a seat in the upper
deck, while anyone taking a short journey can remain on the lower deck
in a similar low-seating configuration to the bendy.

This is true, but I think the main reason bendies are used in London is
to provide rapid boarding and alighting. Judging from the London
Assembly report released today on the value-for-money of quality
incentive contracts, there now seems to be a recognition by TfL that the
rapid boarding and alighting capability should be used on routes used
for short hops, rather than automatically for all high-demand routes,
some of which are characterised by the longer journeys you mention (e.g.
38, 73).

Although German cities may generally be of the model you specify with
near-exclusive penetration of the city centre by rail-based modes, it's
not true of all European cities which use bendies - Rome has poor rail
penetration of the city centre and uses bendy buses from in the inner
suburbs to serve the centre along busy corridors which are not
well-served by rail.

Interestingly, two of the main bendy routes in London (18, Euston -
Sudbury and 25, Oxford Circus - Ilford) are high-demand and yet still
run along corridors well-served by rail compared to other bendy routes
such as the 436 and the 38. I'm not sure what's going on there - I think
perhaps the price differential plays a part on the 18, but I'm not sure
about the 25.

To apply the question to London, then - yes, long-distance routes are
better with deckers. Whether the aim should be to move to a European
interchange model or remain with a British through service model is
another, rather more difficult, question. However, there are routes
where bendies are more suitable, potentially with the appropriate
infrastructure changes. I'd certainly nominate Oxford Street - but
then on the European model, it also needs fewer routes (maybe only
one?) and interchange at convenient points at each end.

As Europe's biggest city, some of the problems facing London are
different to other cities. The expense of providing new rail capacity in
the centre makes through services much more attractive, as a price
differential can be set to discourage use of the faster mode by those
with a lower value of time.

Economically, given rail congestion and the massive cost of providing
new capacity, providing the choice between a fast, expensive mode and a
slow, cheap mode makes a lot of sense - travellers with a lower value of
time can be shifted off the fast mode and onto the slow mode, resulting
in those with a higher value of time experiencing less congestion. The
relief of congestion is a benefit to the high-value-of-time travellers
on the fast mode, and the lower prices are a benefit to the low
value-of-time travellers.

There is one more factor. It is my understanding that the standard
bridge height in most European countries tends to be lower than the UK,
thus DD buses don't necessarily fit. They (and some pretty huge ones
by the typical UK standard) do exist, however - in Berlin, for one.

Neil



--
Dave Arquati
Imperial College, SW7
www.alwaystouchout.com - Transport projects in London