Why does C&NW use ATC between Chicago and Omaha

[Anonymous]

Is their a reason that C&NW uses ATC between Chicago and Omaha I know it came in 1926

[CG9602]

" 'Automatic Train Control protects you in the worst kinds of weather, and materially aids in allowing your train to be brought through on schedule time. It is of immense benefit to shippers in bad weather, especially shippers of perishable goods, as much delay is avoided because the engineer can run at the maximum speed allowable in spite of weather conditions.' ''

from 'Automatic Train-Control - How It Operates on Main Line between Chicago and Omaha, Chicago and North Western Railway," CNWHS, as quoted on pg. 142 of "The North Western," by H. Rodger Grant, 1996.

Why is ti used? That's easy: the volume of traffic warrants its use. one must have some system in place in the event that there is "operator error" by the engineer. By the use of a mechanism that takes away control from theengineer and automaically applies the brakes, this system provides an additional safeguard against collisions. Here's a little bit of trivia: the ATC system that was first installed was technically known as the General Railway Signal Automatic Two Speed Train Control.

[Anonymous]

Thanks CG9602

It benefits shippers form the way it sounds

[jeffhergert]

Except during inclement weather it gets the name "Automatic RAIN Control." One night a couple years back went for about 100 miles and would get train control at every relay box. That night everyone went 39 MPH. At 40 you only have 6 seconds to go to suppression on the train brake. Under 40 you have a little longer and the cab signal might clear up. Seems like the ATC clears up right after the engineer sets air.
Now trains over 5000 feet, except all TOFC/COFC cars, have to stop when they go to suppression over 40mph. Once it awhile doing a running release someone would get a knuckle or broken drawbar.

[jeaton]

Could the answer be "Because its there."?

[eolafan]

"If it aint broke, don't fix it" seems to apply here, and it's much cheaper to leave it in place than to replace it. And please remembers, technology isn't always an improvement!

[CShaveRR]

Keep in mind that elimination of ATC would eliminate any possibility of freights over 60 m.p.h.

It must be too expensive a proposition to convert it to a CCS system compatible with the rest of the UP.

But I can think of at least one instance where even a primitive system like this installed on other Metra lines could have saved a lot of embarrassment (not to mention rebuilding two brand-new locomotives!).

[Anonymous]

CShave or anyone Would You Know how much it would cost to replace ATC and when Amtrak Detours even with CCS would they still need a pilot engining

[jeffhergert]

I don't know the cost of replacing ATC with CCS, but I and others who work with ATC think the UP would have a hard time convincing the FRA to allow this. The ATC is a safer system because it enforces speed control. CCS does not. In CCS you can acknowledge a change of the cab signal to a more restrictive indication, but if you don't slow down it won't take your air.
ATC makes you slow down to 17MPH or less. Over 40MPH if the cab signal goes to restricting you have to make a brake application. Under 40MPH you can acknowledge the change, but if you don't get under 23MPH in a about a minute, or the cab signal clears up, you have to make a brake application. In either case if you don't the ATC will take you air and stop you. You can run between 17 and 23, but you get a constant slow speed horn. After you are running 17 or less the ATC intermittantly needs to be acknowledged or it takes the air.
FYI, the CCS is a 4 indication system: Clear, Advance Approach, Approach, & Restricting.
The ATC is 2 indications: Clear and Restricting.