Re: Train Accident in Blue Mountains

["Bill McNiven" <wmcniven@gunzel.ozemail.com.au>]

David Johnson wrote in message <384FAF93.CA2F10FD@ozemail.com.au>...
>Richard wrote:
>> Valid point...it was along this train of thought that I asked for known
stopping distances for selected speeds. It had
>> occurred to myself as well that maybe the IC wasnt stopping as quickly as
the driver might have liked.
>I'm afraid this will not help much in this case, but I recall that a V set
in emergency from 110 km/h will pull up in
>about 900 metres, approximately twice that of a tangara.


This is the *first* posting on this subject to contain a relevant number
(even an estimate).

110 km/h in 900m implies an accelleration of -0.52 m/s/s, from which one
could extrapolate
m/hr   m/sec   metres  seconds
       5    1.39     1.9     2.7
      10    2.78     7.4     5.4
      15    4.17    16.7     8.0
      20    5.56    29.8    10.7
      25    6.94    46.5    13.4
      30    8.33    66.9    16.1
      35    9.72    91.1    18.7
      40   11.11   119.0    21.4
      45   12.50   150.6    24.1
      50   13.89   186.0    26.8
      60   16.67   267.8    32.1
      70   19.44   364.5    37.5
      80   22.22   476.0    42.8
      90   25.00   602.5    48.2
     100   27.78   743.8    53.6
     110   30.56   900.0    58.9

Food for thought!

Bill