2-6-6-2

2-6-6-2
Diagram of one small leading wheel, two trios of large driving wheels with each trio joined by a coupling rod, and one small trailing wheel
Equivalent classifications
UIC class(1C)C1, (1'C)C1'
French class130+031
Turkish class34+34
Swiss class3/4+3/4
Russian class1-3-0+0-3-1
First known tender engine version
First use1906
CountryUnited States
LocomotiveClass L-1 2-6-6-2[1]
RailwayGreat Northern Railway
DesignerBaldwin Locomotive Works
BuilderBaldwin Locomotive Works
Evolved from0-6-6-0,[2] 2-6-6-0[3]
Evolved to2-6-8-0,[4] 2-8-8-2
BenefitsAble to follow tighter curve than contemporary 2-10-2 locomotives of similar tractive effort
DrawbacksHigher maintenance costs due to a second set of cylinders and valve gear

Under the Whyte notation for the classification of steam locomotives by wheel arrangement, a 2-6-6-2 is a locomotive with one pair of unpowered leading wheels, followed by two sets of three pairs of powered driving wheels and one pair of trailing wheels. The wheel arrangement was principally used on Mallet-type articulated locomotives, although some tank locomotive examples were also built. A Garratt locomotive or Golwé locomotive with the same wheel arrangement is designated 2-6-0+0-6-2 since both engine units are pivoting.

Under the UIC classification the wheel arrangement is referred to as (1'C)C1' for Mallet locomotives.

  1. ^ Mellin, C. J. (1908). Articulated Compound Locomotives. New York, N. Y.: American Locomotive Company. pp. 20–21.
  2. ^ Drury, George H. (2015). Guide to North American Steam Locomotives, revised edition. Waukesha, Wisconsin: Kalmbach Books. p. 181. ISBN 978-1-62700-259-2.
  3. ^ LeMassena, Robert A (1991). Articulated Steam Locomotives of North America, vol. 2. Denver, Col.: Sundance Publications, Ltd. p. 35. ISBN 0-913582-54-9.
  4. ^ LeMassena, p. 103.