What does 4-6-6-4 mean?

Definitions for 4-6-6-4

Here are all the possible meanings and translations of the word 4-6-6-4.


  1. 4-6-6-4(Noun)

    Under the Whyte notation system, a Mallet-type locomotive with four leading wheels on a leading truck, two sets of six driving wheels, and four trailing wheels on a trailing truck.


  1. 4-6-6-4

    In Whyte notation, a 4-6-6-4 is a railroad steam locomotive that has four leading wheels followed by six coupled driving wheels, a second set of six driving wheels and four trailing wheels. 4-6-6-4's are commonly known as Challengers. Challengers were most common in the Union Pacific Railroad and the Clinchfield Railroad. Other equivalent classifications are: UIC classification: 2CC2 French classification: 230+032 Turkish classification: 35+35 Swiss classification: 3/5+3/5 The UIC classification is refined to C2' for Mallet locomotives. One locomotives of the "Challenger" class, Union Pacific 3985 is still operable, and it is currently the largest operable steam locomotive in the world. Another example, Union Pacific 3977 is on static display in North Platte, Nebraska. An expansion for the Union Pacific Challenger class was the Union Pacific Big Boy class, being a 4-8-8-4, instead of a 4-6-6-4. Though originally intended for freight service, many units could be found leading passenger consists as well. Railroads that used the Challenger type locomotive include:


  1. Chaldean Numerology

    The numerical value of 4-6-6-4 in Chaldean Numerology is: 0

  2. Pythagorean Numerology

    The numerical value of 4-6-6-4 in Pythagorean Numerology is: 0

Images & Illustrations of 4-6-6-4

  1. 4-6-6-4


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