Chicago to Florida

[George Harris]

It's just sad. Japan has highspeed

Yes these are the originators of the modern high speed and in many ways the best. They just tend to get overshadowed by our Eurocentric perspective. True, they are not as fast as some of the French lines, but look at the terrain the Japanese deal with.

France has highspeed

True, with astounding little in the way of high technology, IMHO

Germany has highspeed

True, with some interesting points of design.

Australia has highspeed

No, they don't. (Anyone feel free to show me where if I am wrong.)

England has highspeed

One line so far as I know.

Based on the equation for cant on Wikipedia, the maximum degree curve for a 220mph train is 0.2656 degrees with a 6 inch difference in rail height, and 0.3541 degrees for a 9 inch difference. Not sure how that translates into radius of curvature.

As should be obvious from the above, when dealing with very high speeds, calling out curves in degrees gets a little silly. Normally high speed curves are defined by radius. The formula using radius is:

SE = 4.0 V^2 / R

where: SE is balancing superelevation in inches, V is speed in miles per hour, and R is radius of curve in feet.

Normally, if you want to run 220 mph to 250 mph, you would want curve radii of at least 30,000 feet, and 45,000 feet or more would be better.