On July 24, Ed DeRouin asked three questions:
1. Do you know why passenger train speeds were reduced through the
turnouts you mentioned in 1958?
2. In the fall of 1958, did the Q take other actions to reduce passenger
train speeds, similar to question 1?
3. Please explain the difference between lateral and equilateral
turnouts.
Ed, in response to Question 1, I am not sure. Electro-pneumatic straight
air brakes were still in use. Two possible answers are that (1) the Q
decided to quit differentiating between Class A, B, and C passenger trains
at that time, perhaps because steam had all but disappeared, and the speed
defaulted to the lowest speed, or (2) they came to the realization that 50
mph diverging speeds were taking a toll on turnout components.
Regarding Question 2, not that I can find. The Q had already reduced legal
maximum speeds to 79 mph in 1957 everywhere except Aurora to Savanna where
the cab signals allowed them to go 90 mph. Notice that I said legal
maximum.
Regarding Question 3, a lateral turnout is another name for a standard
turnout, with a straight leg, and a curved leg which diverges from the
tangent at the full frog angle. An equilateral turnout has two identical
curve legs which curve in opposite directions. For the same frog number,
the frog angle is the same, but each curve is about twice the radius of the
curved leg of the standard turnout, so the turnout can be negotiated at
higher speed.
Equilateral turnouts became popular at the end of double track where there
was a current of traffic, and where the use of a lateral turnout would
severely penalize all of the trains in one direction, and where a slight
penalty to all trains was more desirable. In reality, railroads also found
that having 100% of the trains diverging at a turnout greatly increased the
maintenance, and the Q quit using them. The BN resumed using equilaterals
in Western Iowa in the early 70's, but also quit using them.
There were 4 equilaterals on Q passenger mainlines that I know of. Number
20 equilaterals were posted for P60/F50, and were installed at Clarke and
Waterworks, Mo., and at Winona Jct. There was a number 15 equilateral in
the EB track at Maxon, IA. (the east turnout of the west crossover) which I
believe was posted for P50/F50. There were also a number of #15
equilaterals south of Bushnell on the line to Centralia.
Glen Haug
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