Re: [Phys-l] truck mileage - a real experiment

[Rick Tarara <rtarara@saintmarys.edu>]

But, of course, this doesn't account for all the variables.  For independent 
truckers, they are paid 'by the load' and even for fleet truckers, the cost 
of shipping will depend on the time (man hours) to ship.  So...if it takes 
you 4 days to deliver a load versus 3 (mandated maximum driving hours now a 
factor) then the fuel savings may be secondary.  For cars, on long trips, 
there is the factor of hours driving (fatigue and possible accidents) and/or 
needing an extra night at a motel for long trips.  The latter will wipe out 
any savings in gas.

Rick (who now prefers traveling back roads at lower speeds--but more to 
escape the tedium of the interstates than to save gas (although that is a 
nice bonus).

----- Original Message ----- 
From: "Laurent Hodges" <lhodges@iastate.edu>


> Back at the time of the "first" energy crisis, in 1973 and following 
> years, the
> speed limit was lowered to 55 miles per hour.  Truckers all across the 
> U.S.
> complained bitterly that this would destroy their livelihood, and that it 
> was
> based on a fallacy, that - for various arcane reasons - the trucks were 
> more
> efficient at higher speeds.
>
> Their protests were so vociferous that the federal government finally 
> carried
> out a real test with real loaded trucks and real truck drivers, sending 
> them
> out over a route on several hundred miles of interstate in Virginia, some 
> each
> sticking pretty much to 60 mph, 50 mph, 40 mph, 30 mph, or some such 
> scheme.
>
> The 30 mph speed was the most efficient (surprise!), followed by 40 mph, 
> 50
> mph, etc.
>
> That pretty much shut up the truckers, who didn't like the implications. 
> It
> could have been worse: they could have tried 20 mph, too.