Re: Train Accident in Blue Mountains

[Dion Williams <onamission@start.com.au>]

Bill Bolton wrote:

Dion Williams wrote:

> > If the impact had occurred at low speed the force could have been readily
> > absorbed by the mass of the train in front.
> 
> Really, how do you figure that?  The IP locos had reportedly just
> started to move so the slack was probably still bunched for most of
> the 17 car train.

Thus a significant portion of it, probably more than the weight of the
IU, was still at stop and able to absorb the force of the impact via
slack couplings. The damage done to both trains suggests I would think a
speed that compensated for the large mass difference. Even eight IP cars
plus motorail would be significantly heavier than a four car V set.

> > over to derail its front car and the IP's rear wagon across the adjacent
> > track.
> 
> Since the collision was on a sharpish curve, that was an almost
> certain outcome from a collision at anything other than a trivial
> speed.

Any derailment yes. A derailment causing both vehicles to be left
leaning at 30 degree angles, intermeshed for approximately five metres,
blocking both running lines, I would think requires something more.

> > Media reports indicated there were approximately six seconds between the
> > driver sighting the danger at 100m and the impact.
> 
> The Sydney Morning Herald wrote piece, which was a entirely
> speculation, about how little time the driver had to warn the
> passengers.  AFAIK the driver has said nothing about the incident.
> 
> So the 6 second figure is not based on any known fact at this stage
> and further more does not tally well with reports from "eye/ear
> witnesses" at the site or on the IC at the time of the collision.

Quite possible and I did note this was not reliable evidence.

> Remember, not only did the driver have time to warn passengers, but
> another male passenger had time to start warning the upper deck
> passengers based on the drivers warning, so there were two sets of
> reaction times involved for the upper deck warning.  For this all to
> occur within 6 seconds would be a truly remarkable event.

On the other hand it was a short enough period for the passengers in the
front middle deck area of the leading IU car to be unable to move from
their positions prior to the impact, something that would not have been
as greatly impeded by the force of braking from a low speed as from a
high speed. Perhaps they did not fully realise the danger they were in. 

Dion