CLASS: D11a. Camelback 4-6-0.

Based on text by Omer Lavallée


Taken from Spanner Magazine, Collectors' Item - 18 by Omer Lavallée

One of the more classic versions was the "camelback", recognized by the positioning of the cab astride the boiler. In some applications in the United States, where such locomotives enjoyed much more use than in Canada, the rear cab was little more than a rudimentary shelter.

This type developed as a result of the use of anthracite coal as a fuel. To obtain satisfactory results from hard coal, a wide and shallow firebox was desirable, and the dimensions of the firebox were extended practically to the full clearance limits of width. With such a wide firebox (see photograph), the cab could not be placed effectively over the firebox and boiler backhead; the alternative was to move it forward over the boiler mid-section which was of normal diameter.

There were disadvantages, of course. One was the fact that the engineman could not readily communicate with his fireman. Another was the small and confined space on each side of the boiler, which soon resulted in the nickname "Mother Hubbard," because of the cupboard-like cramped quarters.

Hundreds of camelback types were used in the New York area. They drew their fuel from the extensive anthracite mining areas of Pennsylvania. Canadian Pacific experimented with this design on six locomotives. A 2-8-0 type built for the Company by the Richmond Locomotive Company in Virginia in 1899, No. 1026, was the first. The results encouraged the Company to build five 4-6-0 type engines in 1905, one of which is illustrated above. These D-11-a class locomotives were, in all other respects, the same as conventional D-10 class engines then being introduced.

After two years of further tests, the decision was made to convert the D-lls into conventional D-lOs, as the camelback did not appear to hold much promise for Canadian Pacific. They were rebuilt in 1907 and served out working lives varying from 30 to 50 years without visible differentiation from the other 497 locomotives in the D-10 class.

Numbers CP 780 - CP 784
Number of locos built in this class 4
Builders CPR Angus Shops
Years Built 1905
Type Camelback Type 4-6-0
Cylinder size ##x## cm (21x28 inch)
Driving Wheel diameter ### cm (63 in.)
Total Weight (with Tender) ###,###-###-### kg (314,700 lbs.)
Extreme length (Including tender) n/a
Extreme Height n/a
Original cost $n/a

 

Preserved: None