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The US is optimized for very heavy freight cars moving at about 45 mph. It has fairly sharp curves so that changes of elevation (grades) can be minimized, it us
by Merrill 7y ago
The US is optimized for very heavy freight cars moving at about 45 mph. It has fairly sharp curves so that changes of elevation (grades) can be minimized, it usually has wooden railroad ties, and street and highway crossings are allowed.
Much of the system is single track allowing train movement in one direction at a time, while trains going in the opposite direction idle in sidings. This is the result of the railroads being charged property taxes on their railways, which they minimized by tearing up double track unless it was absolutely needed.