Re: English Railway Accident

["chris 'fufas' grace" <chris@transdata.co.nz>]

keith malcolm wrote:
> 
> chris 'fufas' grace <chris@transdata.co.nz> wrote in message
> 3A9F45A4.CD7EFD45@transdata.co.nz">news:3A9F45A4.CD7EFD45@transdata.co.nz...
> > keith malcolm wrote:
> > > My impression was that the comments were made purly in relation to
> propelled
> > > trains, (DVT, carriages, loco/power car) not push pull trains (loco,
> > > carriages, loco), in which case I agree a train like that is unstable,
> what
> > > happens if the front derails and the rear keeps applying power?
> > >
> > > Dave Malcolm
> > >
> >
> > I think you have your definitions mixed up. The DVT/Coaches/Loco
> > combination is push-pull by definition. A train with power cars at
> > each end is a unit train in which some of the cars are being pushed
> > and some pulled at any give time whilst it is moving. Power
> > differences between the two power cars make sure of that.
> 
> No I don't. A DVT is a Driving Van Trailer. Trailer as in un powered. So it
> is not push pull, it is propelled but controlled from the front.

Yes you do. You have just described classic push-pull operation. When
the DVT is at the front of the train, it is being pushed. When it's at
the back, it's being pulled. Exactly the same as the original push
pull with a steam engine at one end and a driving trailer at the
other.

Or do you think the trains are remarshalled at each terminus so that
the DVT is always at the front?

For the full story, see:
http://www.trainweb.org/railwaytechnical/pu-pl.html

Disclaimer: ALthough this is not my site, I wrote this page after
substantial research.