Re: Glenbrook train was travelling about 37kmh at time of crash: expert

["ERIKA" <torpan@myrealbox.com>]

Amazing,fellows, i agree.
Yes it is about time that the bureaucrats and politicans do something
constructive instead of relying on "UK experts"There is a wealth of talent
in this country in a quite a number of fields.Im sure the comparable
expertise is out there in private enterprise to give a professional opinion.
The other day i spoke to a lady friend of mine whose husband came from
Holland--he is a test pilot and compatable expert in the aviation
industry.What happens he has to go overseas to work while in Australia.
The unfortunate happening at Glenbrook being investigated technically by the
English is draconian and stiffling the talent which surely we have here.

--
Erika<erika@torpan.com>
Manly,Sydney,Australia.
<homepage at<www.torpan.com>
Fax:::1 9492 776387
ViaGodias
"Chris Parnell" <chris@infinisource.com> wrote in message
953754500.847693@clover.river.net.au">news:953754500.847693@clover.river.net.au...
> Why do we have to get experts from overseas to come here and investigate
> what we do and tell us how to get it right; in particular, experts from
the
> UK?
>
> I am not into Pommy bashing here, I just ask the question; do we not have
a
> sufficently well trained cadre of accident investigation experts in this
> country?
>
> I reckon we could do this ourselves; can we really become a republic and
> continue to tug our forelocks to Mother England and her experts? Or is
this
> cultural inferiority burnt deep into our psyche?
>
> Chris Parnell
>
> C. Dewick <craigd@lios.apana.org.au> wrote in message
> news:8b98kr$nfp$1@jedi.apana.org.au...
> > "Gnome 412" <gnome412@hotmail.com> writes:
> >
> > >from http://www.smh.com.au/breaking/0003/21/A21846-2000Mar21.shtml
today
> ...
> >
> > >Source: AAP | Published: Tuesday March 21, 12:07 PM
> >
> > >The commuter train involved in the Glenbrook disaster was travelling at
> an
> > >estimated speed of 37kmh when it hit the Indian Pacific, a British
expert
> > >said today.
> >
> > >Kevin Thomas Crofts, a mechanical engineer who has worked for 20 years
> > >studying the structural integrity of trains was brought out to
Australia
> > >from Derby, England to examine the aftermath of the December 2
collision.
> >
> > >The collision near Glenbrook in the New South Wales Blue Mountains left
> > >seven people dead and 51 injured.
> >
> > >Mr Crofts told the inquiry into the crash he used five factors to
> estimate
> > >the speed of impact: the extent of the damage, the gradient of the
track,
> > >the braking performance of the interurban train, the time delay between
> the
> > >driver applying the brakes and them coming into effect and the reaction
> time
> > >of the driver.
> >
> > But he forgot to take into account the environmental conditions around
the
> > track in the cutting which may have a critical effect on the braking
> > performance of the train.
> >
> > I still stand by my original claim that it is *impossible* without
> intensive
> > analysis (and five factors do not make for intensive analysis) of
> everything
> > involved.
> >
> > And regardless of what Mr Crofts has determined, even he has said it's
an
> > 'estimated' speed. I guess it's probably the best official estimate
we'll
> > get.
> >
> > We can safely assume that there would have some speed reduction prior to
> > impact owing to the time which elapsed between the driver leaving the
> > controls in emergency braking (either by actual moving the brake handle
to
> > 'emergency', or by releasing the master controller handle, or both) and
> > getting out of the cab into the main body of the car.
> >
> > So this raises the next question - if Mr Crofts says the train was
> estimated
> > as doing 37 kph when it hit the IP, how does he know for certain what
the
> > speed vs distance curve was for the few seconds between the driver of
the
> > intercity train becoming first aware (ie. when his brain processed the
> > visual information about the IP in front and started the neural
processes
> > off to take the necessary physical actions) and when the train actually
> > collided with the IP?
> >
> > He doesn't.
> >
> > >If the interurban driver reacted 0.4 of a second after seeing the
Indian
> > >Pacific on the track ahead of him, and the Indian Pacific was
travelling
> at
> > >6kmh Mr Crofts said the impact speed was in the range of 34-41kmh.
> >
> > 0.4 seconds is pretty fast don't you think? Most people have an average
> > reaction time of between 0.7 and 1.5 seconds depending on their level of
> > alertness, etc. so I find the figure of 0.4 seconds extremely
optimistic.
> >
> > >'The most probable actual velocity was probably around 37kmh,' he told
> the
> > >special commission of inquiry into the crash.
> >
> > >Mr Crofts said the interurban train was likely to have been travelling
at
> a
> > >speed of 53.5kmh when the driver first spotted the Indian Pacific ahead
> of
> > >him.
> >
> > Ah - here we are... Ok, so the train is claimed to have reduced speed
from
> > 53.5 kph (14.86 m/s) to 37 kph (10.27 m/s) between when the emergency
> brake
> > was applied and when the two trains hit. Over what distance did the
> > intercity train travel between these two points? I would estimate, given
> the
> > grade, etc. that the maximum deceleration under emergency conditions
would
> > not be more than about 0.6 m/s/s. Does anyone have accurate data that
can
> be
> > used to do some test-calculations?
> >
> > Sounds quite unlikely that the train could have been doing anywhere near
> 50
> > kph, or else the distance required to reduce speed to 37 kph would be a
> lot
> > larger than the actual distance involved in this incident unless the
rails
> > were totally dry and the train didn't skid or slip once the emergency
> brakes
> > were fully applied.
> >
> > >He said the damage was intensified because the Indian Pacific's last
> > >carriage, a car carrier, and the interurban carriage were of different
> > >structures.
> >
> > Well what's so unusual about that? It's not something we didn't already
> now
> > by simple observation. 8-)
> >
> > >Very little of the energy of the crash was absorbed by the Indian
Pacific
> > >car carrier.
> >
> > Once again, we already knew that.
> >
> > >'It was all taken by the passenger vehicle,' Mr Crofts said.
> >
> > Again, something we already knew. I guess the person running the inquiry
> is
> > supposed to be impartial and not know anything about mechanics...
> >
> > Regards,
> >
> > Craig.
> >
> > --
> >             Craig Ian Dewick            |       Stand clear - jaws
closing
> >  Send email to craigd@lios.apana.org.au |  Visit my Australian rail
> transport
> >    Professional Train Driver, Cityrail  |      and rail modelling web
> site:
> >        and HO scale rail modeller       |
> http://lios.apana.org.au/~craigd
>
>