Baldwin Class 10-12-D

The Baldwin Class 10-12-D was a class of narrow gauge 4-6-0 pannier tank steam locomotives built by the Baldwin Locomotive Works (USA) for the British War Department Light Railways for service in France during World War I. They were built in 1916-1917 to RailGauge|600mm gauge.

Dimensions

* Locomotive weight, 14 tons 10 cwt (Note 1)
* Water tank capacity, 476 U.S. gallons (1802 L)
* Coal capacity, 15 cwt (Note 1)
* Boiler pressure, 178 psi (1.23 MPa) (Note 2)
* Superheater, No
* Cylinders, 9"x12" (229 mm by 305 mm)
* Driving wheel diameter, 1' 11½" (597 mm)
* Tractive effort, 6,258 lbf (27.84 kN)
* Valve gear, Walschaert (slide valves)

* Note (1) It is uncertain whether weights are in short tons or long tons, but the use of cwt is a hint that it might be long tons.

* Note (2) Why is the boiler pressure not 175 or 180 psi? Baldwin had previously built some similar locomotives for the Chemin de fer Militaire de Maroc Occidentale (Military Railways of Western Morocco) and these would have been built to metric dimensions. The figure of 178 pounds per square inch is almost exactly 12.5 kilograms-force per square centimetre so this may be the explanation.

For terminology, see Steam locomotive components

Origins Of The Type

History of the class 10-12-D is more compicated than usually known.

The French ( or actually the Belgians ) had designed 600 mm gauge 2Ct-n2 locomotives as earlyas in 1900-1901 for Chemin de Fer du Calvados. The prototype was Tubize factory type 73.
Weidknecht used these drawings and built similar 11 ton locomotives with subcontractedboilers, presumably built by S.A.Energie, Marcinelle.

Tubize 1209 / 1900 600 ( Factory type 73 ) 230x305 600 C.F.du Calvados No 103

Tubize 1240 / 1903 600 ( Factory type 74 ) 230x305 600 C.F.du Calvados No 104

Tubize 1241 / 1903 600 ( Factory type 74 ) 230x305 600 C.F.du Calvados No 105

Tubize 1242 / 1903 600 ( Factory type 74 ) 230x305 600 C.F.du Calvados No 106

Tubize 1243 / 1903 600 ( Factory type 74 ) 230x305 600 C.F.du Calvados No 107

Tubize 1244 / 1903 2Ct-n2 600 ( Factory type 74 ) 230x305 600 C.F.du Calvados No 108

Tubize 1620 / 1909 2Ct-n2 600 ( Factory type 74 ) 230x305 600 C.F.du Calvados No 109

Weidknecht 689 / 1902 2Ct-n2 600 230x305 600 C.F.du Calvados No 9"

Weidknecht 690 / 1902 2Ct-n2 600 230x305 600 C.F.du Calvados No 10

Weidknecht 691 / 1902 2Ct-n2 600 230x305 600 C.F.du Calvados No 11

Weidknecht 698 / 1902 2Ct-n2 600 230x305 600 Tramways a Vapeur du Tarn No 4

Weidknecht 699 / 1902 2Ct-n2 600 230x305 600 Tramways a Vapeur du Tarn No 5

Weidknecht 751 / 1907 2Ct-n2 600 230x305 600 C.F.du Calvados No 12

Weidknecht 752 / 1907 2Ct-n2 600 230x305 600 C.F.du Calvados No 13

Weidknecht ..... / 1908 2Ct-n2 600 230x305 600 C.F.du Calvados No 14

Weidknecht ..... / 1913 2Ct-n2 600 230x305 600 Tramways a Vapeur du Tarn No 6

The French military circles become interested of this 2Ct-n2 locomotive type for their
Decauville Light Military Railways in Morocco. A little heavier 14 ton type was designedand an order was placed for Weidknecht to produce these locomotives for the 600 mm gaugelines in Morocco.

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Marnia - Taourirt No W 1

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Marnia - Taourirt No W 2

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Marnia - Taourirt No W 3

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Marnia - Taourirt No W 4

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Marnia - Taourirt No W 5

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Casablanca - Rabat No 1

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Casablanca - Rabat No 2

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Casablanca - Rabat No 3

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Casablanca - Rabat No 4

Weidknecht ..... / 1912 2Ct-n2 600 230x305 600 C.F. Casablanca - Rabat No 5

Weidknecht delivered 20 more in 1913 - 1914 for Chemins de fer Militaires du Marocnumbered ( 1 - 20? ).

Baldwin and ALCo Built Locomotives

When the Great War broke out in August 1914 the French lost most of their locomotivebuilding capacity in the Northern France to German occupied area. Therefore the French Armydemanded fast replacemant of the locomotive building capacity for their useful 2Ct-n2 typewhich had proved to be a reliable locomotive type for the lightly laid military railways.

Three steam locomotive type drawings were sent to Baldwin Works ( finance quaranteed by theFrench Government ) for production of Ct-n2, "2Ct-n2, and light Mallet B´B-n4v for 600 mmgauge lines. With the usual American liberty Baldwin Drawing Office produced their " versionAmericaine " of these locomotive types. The first Ct-n2 ( based to Decauville design )came out in November 1914 and the first batch of 2Ct-n2 in January 1915.

Baldwin 41897 - 41902 / 1915 600 229x305 597 French Government No 101 - 106 Morocco

Only two more batches were built for the French.

Baldwin 44178 - 44182 / 1916 600 229x305 597 French Government No 107 - 111 Morocco

Baldwin 51569 - 51573 / 1919 600 229x305 597 French High Commissar, Morocco No 112 - 116

The reason why the British War Office decided to be the principal military steam locomotivetype, remains unknown, but the Baldwin started production in 1916.

Baldwin 44335 - 44339 / 1916 600 9x12 23.5 British War Office No 501 - 505

Baldwin 44351 - 44390 / 1916 600 9x12 23.5 British War Office No 506 - 545

Baldwin 44489 - 44494 / 1916 600 9x12 23.5 British War Office No 701 - 706

Baldwin 44507 - 44556 / 1916 600 9x12 23.5 British Government No 707 - 756

Baldwin 44635 - 44659 / 1916 600 9x12 23.5 British Government No 757 - 781

Baldwin 44681 - 44689 / 1916 600 9x12 23.5 British Government No 782 - 789

Baldwin 44695 - 44794 / 1917 600 9x12 23.5 British Government No 790 - 889

Baldwin 44891 - 44901 / 1917 600 9x12 23.5 British Government No 890 - 900

Baldwin 44938 - 45037 / 1917 600 9x12 23.5 British Government No 901 - 1000

Baldwin 45133 - 45236 / 1917 600 9x12 23.5 British Government No 1001 - 1104

Baldwin 45347 - 45383 / 1917 600 9x12 23.5 British Government No 1105 - 1114

Baldwin 45398 - 45433 / 1917 600 9x12 23.5 British Government No 1115 - 1150

At this point the production was changed to American Locomotive Company but locomotives were built after the Baldwin drawings.

ALCo 57092 - 57191 / 1917 600 9x12 23.5 British War Office No 1201 - 1300

Some of the class found during war their way to other theatres of war than Europe.

Baldwin 45163 - 45222 from batch No 1001 - 1104 were renumbered by the British War Officeto War Department Light Railways, Middle East No 581 - 640 and were shipped to Egypt to be used in Sinai and Palestine during the British 1917 offensive against the Turks. After the war most of them remained in Middle East.

Peacetime service

After the war many of these locomotives were sold and went on to work in France, Britain and India. Indian North Western Railway received fifty locomotives and numbered them to NWRNo 1 -50. Unfortunately their later fate is mostly unknown. British narrow-gauge railways which used them included:

* Welsh Highland Railway
* Glyn Valley Tramway
* Snailbeach District Railways
* Ashover Light Railway

Preservation

Three Baldwin Class 10-12-D locomotives have been preserved in the UK:

* No. 778, Leighton Buzzard Light Railway
* No. 794, Welsh Highland Railway
* there is no evidence for the third - see discussion

ources

* Light Railways of the First World War by W. J. K. Davies, published by David & Charles, 1967