In article ,
David Hansen wrote:
On Wed, 10 Nov 2004 20:39:08 +0000 someone who may be Clive Coleman
wrote this:-

I suspect the shape of the leading power car to have something to do
with gathering up the car instead of just shunting it to the side.

As has been said before, the shape of the nose of the power car is
simply fibreglass. Behind that fibreglass is essentially what one
would find on the front of a locomotive, though without the buffers.


It does seem that most of the car wreckage was tossed aside very close to
the point of impact on the crossing. But I guess that something (the
engine perhaps ?) must have caught underneath and derailed the leading
wheelset.

David

Clive Coleman wrote:
In message , dwb
writes
econdly, the rear power car was NOT under the full power.
The train's 'black box recorder' that the power notch was at zero
and the brake handle was in 'emergency'. It was simply the inertia
of the rear power car (which had already derailed) that kept it
moving.
Do you KNOW that?

Um... I didn't write that.

ANyway, as David says, it's in the HSE report so I would guess it might be
true.

Ronnie Clark wrote:
Clive Coleman wrote in message:

I don't troll this N/G but I do remember working on British Railways
when propelling was not allowed above 40mph. I expect I'll now get
some egghead to troll me, but this was always the case when working
tender first. (It also had the advantage of keeping the coal dust out
of your eyes).


Generally 45mph now for tender engines working backwards (at least, in all
the tender engines I've been in).

However, do note that this was not due to the dange of derailment. It was
due to poor visibilty.

Do remember that push-pull services with tank engines existed for a long
time during the big-four period and continued into BR days. These were not
troubled with visibility problems, as the driver could control the engine
from a suitable front coach - something which could be called the very first
DVT, but better known as the auto-coach

Not much of a van, though. More like the DBSO on Liverpool St - Norwich
(not for too much longer).

Robin

Richard J. wrote:

The unfounded idea that the rear power car was still under full power
was certainly NOT in the interim HSE report. It was an ignorant rumour
that I believe was mentioned first on Sky News a few hours after the
crash.

Why would any sane person believe anything from the Murdoch organisation?

Brian Rumary, England

http://freespace.virgin.net/brian.rumary/homepage.htm

Clive Coleman wrote to uk.transport.london on Wed, 10 Nov 2004:

I don't troll this N/G

Which N/Gs do you troll, then? (Sorry, couldn't resist!)
--
"Mrs Redboots"
http://www.amsmyth.demon.co.uk/
Website updated 6 November 2004 with new photos

David Hansen wrote:

Clive Coleman wrote:

secondly, the rear power car was NOT under the full power.
The train's 'black box recorder' that the power notch was at zero and
the brake handle was in 'emergency'. It was simply the inertia of the
rear power car (which had already derailed) that kept it moving.

Do you KNOW that?

The Railway Inspectorate say so in their interim report.

Unless you are reading a different report than is available on the RI
web site:

- There is no mention of the power setting in the interim report.
- There is no mention of the type of brake application, nor the position
of the brake handle in the interim report, only that the brakes were
applied 2 to 3 sections prior to impact. One can assume they were
applied in emergency, but the report makes no statement on the subject,
and it would be an assumption on the part of the reader.
- There is no mention in the report of where the rear power car first
derailed, (meaning the one at the London end of train) only that it was
derailed where it came to rest.

How do people get so many facts wrong, when the report is readily
available?

Tim Christian wrote:

Braking and power control not withstanding, a heavy weight at the rear of a
train is not good news when it has to stop in a hurry,

It makes absolutely no difference what the distribution of weight in the
train is when stopping in a hurry. The suggestion that the locomotive in
the rear is somehow a problem demonstrates a complete misunderstanding
of the physics involved.

The issue is the total mass of the train behind a derailed vehicle,
which includes the mass of the coaches as well as the power car. That
total mass is what creates the tendency to jackknife. The only way to
avoid it is to run separate, individual vehicles, since there would then
be nothing to push from behind. Individual vehicles are what run on
highways. Trains run on tracks.

but a heavy weight at the front means a better chance of staying
upright and, potentially, more protection for the guy at the sharp end.

That is true, since a heavy vehicle is more likely to remain on the
rails, rather than be lifted up in a collision and derail. However, just
because a vehicle is heavy doesn't necessarily mean that it offers more
protection. I acknowledge that you said "potentially", since the weight
can be from other things than extra strength applied to the front
structure of the vehicle, which would provide the necessary protection.

In message , James Robinson
writes
That
total mass is what creates the tendency to jackknife. The only way to
avoid it is to run separate, individual vehicles, since there would then
be nothing to push from behind. Individual vehicles are what run on
highways. Trains run on tracks.


Don't say that too loudly otherwise the media and safety mafia will be
screaming for all real trains to be replaced by dogboxes! :-)
--
Spyke
Address is valid, but messages are treated as junk. The opinions I express do
not necessarily reflect those of the educational institution from which I post.

In message , Mrs Redboots
writes
Clive Coleman wrote to uk.transport.london on Wed, 10 Nov 2004:

I don't troll this N/G

Which N/Gs do you troll, then? (Sorry, couldn't resist!)
Uk.transport.
--
Clive Coleman

Roger H. Bennett wrote:
"David Hansen" wrote in message
news
Even if it was under full power the extra force that provided was
not enough to cause the damage. If it was then HSTs would be damaged
every time only the rear power car is working, which happens from
time to time. The forces the power cars produce are minor compared
to the forces involved in a crash.

Quite. The maximum tractive effort is about 8 tons, which I guess (I
don't have a power curve) would be only about a quarter of that at
100 mph. Compared to the momentum of its 70-ton weight at 100 mph,
plus that of the other carriages at the rear, the effect of any power
it could produce is negligible.

Roger

Power was cut, full emergency brake was in and the power car at the rear
provided much additional braking effort to the rear five coaches, which
did not pile up onto the front three. The driver did everything right,
call it self preservation, instinct, skill whatever, it is a testament
to his last act and the construction of the train that so many survived.