[PRCo] Fw: 4-8-4 passenger speeds?

[Jim Holland]

wrote in message news:...
 > In article <1190832083.423168.115180 at 50g2000hsm.googlegroups.com>, Paul
 > wrote:
 >
 > > On a recent Empire Builder trip to Glacier Park, we saw in Havre Mt a
 > > parked Baldwin steam loco. I believe it was 4-8-4, with 80" drive
 > > wheels.
 > >
 > > I was wondering whether one of those monsters would have pulled our
 > > current Amtrak 11-car consist at current 80mph speeds?
 >
 >
 > Yes.
 >
 > In the "old days" of steam (before the "modern" steam era when 
everything
 > was carefully engineered) the general rule was that the maximum safe
 > operating speed in miles per hour was equal to the size of the 
drivers in
 > inches.
 >
 > So, even using that rule (which turned out to be overly conservative in
 > the later decades of steam operation) a locomotive with 80 inch drivers
 > would operate a train at 80 mph.
 >
 > As the engineering got better and better, the speeds got faster without
 > increasing the driver diameter.
 >
 > The Hiawatha locomotives owned by Milwaukee Road, for example, had to
 > operate at 100 mph just to keep the timetable but had drivers in the
 > approximately 80 inch range.
 >
 > --
 > -Glennl
 > e-mail hint: add 1 to quantity after gl to get 4317.
.
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^~^~^~^~^~^~^~^~^~^
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Jim  Holland
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Studying Pittsburgh Railways Company (PRCo)
.
..............................From 1930 -- 1950
.
Pennsylvania  Trolley  Museum  (PTM)
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http://www.pa-trolley.org/
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N.M.R.A.
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http://www.nmra.org/