Steam & Excursion > Class vs. Cabside Class

I discovered recently that the Union Pacific, in addition to classes, had “cabside” classes for their steam locomotives.

For example, UP 0-6-0 #4466 is an S-6 class, but also an S-51 cabside class.

What is the difference between class and cabside class?

Thank you.

Posted from iPhone

My guess...( being an Easterner)

Possibly a question about late-UP steam locos & cab-side class I.D.?

Might also be helpful in filling-out crews' time sheets, especially since 
their pay was partly determined by weight on drivers...which they would 
enter on the daily timesheets..

The 'coding' simplified the loco description particulars...for payroll dept.

W.

From Trains mag on line:

Question: What do the numbers and letters mean on the side of the cab of
loUnion Pacific Challenger 4-6-6-4 No. 3985? — Ben Fairbank, San Antonio, Texas "Answer:
                     21 – 21
4-6-6-4-4-69 ————— 404 32
The number, 4-6-6-4 is the wheel arrangement. The extra “4” on the end notes
that No. 3985 was part of the fourth of five orders of Union Pacific Challengers.
The 69 is the diameter, in inches, of the driving wheels.The fraction describes the drive cylinders:
both the front and rear engines have cylinders 21 inches in diameter,
each with a 32-inch stroke.

Finally, the “404” refers to the weight of the locomotive, in thousands of pounds."

W.



Edited 2 time(s). Last edit at 03/29/24 00:28 by wcamp1472.

Wes,

That "404" on the UP Challenger indicates weight ON DRIVERS.