Minimum distance between track cant changes

[eMeS]

Just wondering if there are any places on the WCML where the tilt (cant) in the track changes direction so that the front part of a Pendolino is tilting one way, whilst the trailing end should be tilting the other way? As trainsets are lengthened I guess this becomes more of an issue. Is it an issue at the moment?
Subsidiary question: Can Pendolinos tilt both ways at the same time?

 

[PaxVobiscum]

...Subsidiary question: Can Pendolinos tilt both ways at the same time?

I don't know, but I've seen people on a Pendolino who looked like they were.

 

[Old Timer]

There are several sections along the WCML where this will happen. One very obvious location is on the Up Birmingham running onto the Up Birmingham Flyover at Rugby Trent Valley Jct where the base of the Flyover is reached by a reverse transition, so the front of the train can be on the r/h, the middle on the l/h and the rear on the r/h exit.

 

[themiller]

Probably in the Lune Gorge in Cumbria as well.

 

[PaulLothian]

Some video on Youtube that suggests they can and do:
http://www.youtube.com/watch?v=padV6STbuLc
http://www.youtube.com/watch?v=D40gvPWNx1c

On a related theme, could a Pendo theoretically iron out the reverse cant at Carstairs on the Edinburgh line into the station?
http://www.youtube.com/watch?v=Otg8RlLIXEM&feature=related.

 

[Trog]

Think how little straight track there is on the WCML. So there will be a lot of reverse transitions where the cant runs down to zero then up on the other rail, as the curve changes hand. In fact I would not be surprised to find out that there were more of them than curved to straght transitions.

 

[eMeS]

Many thanks for all your replies. I'm much wiser now!

Here's the image which got me thinking about this - taken looking north from Platform 4 at Wolverton Station. (I normally keep my long lenses for bird photography, but my 400mm did well on this shot.)

 

[jopsuk]

I'm curious- were reverse curves such as this part of what cuased the APT's tilt system problems?

 

[Wyvern]

The whole point of the tilt system whether APT or Pendolino is to deal with such curves.

Dont forget that photo has been taken with a long lens.

 

[Bald Rick]

I'm curious- were reverse curves such as this part of what cuased the APT's tilt system problems?

No. Two main problems - 1) it was new technology that took a while (several years) to perfect; 2) the APT fully compensated for the cant deficiency in the curve i.e. you couldn't tell you were curving or tilting at all. This caused motion sickness in all but the hardiest sailors. The Pendolinos only partly compensate for the curve - 75% I think - which solves it for most people. Including me, and I've been seasick on a boat moored on the Thames.

 

[Wyvern]

I have to say even on a Pendolino the first time I saw all the lamp posts on a motorway we were passing all leaning over at a drunken angle I felt decidedly queasy.