"Andrew P Smith" wrote in message
...
In article , Stephen
Far easier to do what has been
done on the JLE and get the platforms etc right first time.

That was what I meant, that track can be positioned accurately relative to
the platform edge, and prevented from moving. Given a straight platform
this can bring the vehicle entrance very close to the platform edge, and a
wheelchair can easily board. At existing stations which have tightly curved
platforms it is not possible to avoid a gap which is too wide for a
wheelchair to cross, but if the track is accurately positioned, so that the
width of the gap is known, and constant, then I think that a device working
on a similar principle to the New York gap filler could be designed to allow
a wheelchair to board, and at a cost which would be affordable, which total
reconstruction of the station, and the approach tracks leading to it, to
eliminate the curved platforms would not be. If it is not possible to
arrange for the vehicle floor to be exactly level with the platform surface
then, as long as the difference is fairly small, known, and constant, then I
think that a tilting gap filler could be designed, which would form a ramp
as it extended.

In an ideal world we would have anunderground system where all platforms
were suitable for wheelchair access to trains, but in reality, the cost of
the reconstruction which would be needed at some stations would be so high
that it could never happen. In some circumstances this may be an affordable
alternative.