Mesopotamia/ Iraqi State Articulated Locomotives in Iraq

Class M (Locobase 14395)

Data from DeGolyer, Volume 57, pp. 311+; and P Allen Copeland, "Baldwin 0-6-6-0 Locomotives Sent to Chile", unpublished manuscript dated 6 June 2009, supplied by Allen Stanley in August 2013 from his extensive Rail Data Exchange collection. See also "Mesopotamian Railways--Opening of the Basrah-Baghdad Ry", Locomotive Magazine, Volume XXVI [26] (14 August 1920), p. 168; and AM Bell, "Oil-Burning Locomotives in India and Mesopotamia", Railway Engineer, Volume 42, No 7 (July 1921), pp. 247-250; and Richard Coke, "The Railways of Mesopotamia", Railway Magazine, No 370 (April 1928), pp. 255-264. Works number 47286-47287, 47385-47388, 47432-47433, 47471 in December; 47539-47543, 47606-47607, 47686-47687, 47738-47739 in January 1918; 47778-47779, 47908-47909, 47966-47968 in February; 48020-48022, 48065-48066 in March; 48193 in April; 48251, 48939 in June; 48990, 49152, 49241, 49361 in July.

This batch of Mallets was the lion's share of a design originally ordered by the Russian government. With the coming of the Russian Revolution in November (Julian date: October) 1917 and the cancellation of orders for hundreds of locomotives, Baldwin found a ready buyer in the Middle East.

The sale went through the British War Mission for France in March 1918 and included a change from the 3 foot, 6 inch (1,067 mm) cape gauge to metre gauge. As in the other ex-Russians, high-pressure cylinders received their steam through 8" (203 mm) piston valves; Low-pressure cylinders used Richardson balanced slide valves.

Bell's detailed 1921 report on oil-burning locomotives commented (p. 249), that the use of oil in locomotives in Mesopotamia seemed "most attractive" given the immediate availability in nearby oil field. But the motley collection of locomotives delegated to the area were so worn that "conditions for a change to oil fuel were as bad as they could be."

Yet the boilers suffered most from the bad water quality and "as oil-burning locomotives evaporated more water than coal on the account of the necessity for supplying the steam to the burners", Bell concluded, there was "no doubt these engines were seriously affected." More could have been achieved, he added, had the water not been so bad or if it could have been treated (both French and US railways made extensive use of water treatments in later years).

Properly outfitted, Bell wrote, "a very considerable economy" could be achieved through oil-firing. The Mexican trough method worked well. The burner in the firebox had to be placed no less than 9" (229 mm) above the firebricks. Moreover, failure to provide a "sufficient [vertical] distance" between the burner and the lowest row of firetubes (i.e. a "satisfactory capacity for the combustion space") meant that results would fall short "as regards oil consumption or steaming power."

Conflicting with the post-war report detailing Baldwin's oil-burning setup is the 30 March 1918 Extra Work order #3500 described in Baldwin's own specification. It noted that the locomotives' new owner--the British War Mission for France--requested that all of the oil burning equipment and the oil tank replaced by all the components--grate, ash pan, smokebox details and tool equipment--needed to burn coal. .

Richard Coke's 1928 report in Railway Magazine didn't say which fuel was used, but observed that for "some time, the premier engines in use on the metre gauge were ...0-6-6-0s ... A one time the principal trains were almost invariably 'horsed' by one of them, but their extravagance in fuel deprived of their honourable position." He added that "Oil fuel is used exclusively on the whole system and its high first cost forms one of the major difficulties in the economic workings of the system."

All were out of service by World War II.