Data from "Heavy Locomotives for the Londonderry and Lough Swilly Ry," Locomotive Magazine, Volume XVIII (15 October 1912), p. 207. See also R M Livesey, "Rolling-Stock on the Principal Irish Narrow-Gauge Railways", Engineering, Volume 94, (2 August 1912), pp. 169-176, table on p. 175. Works numbers were 746-747 in 1905.
A rarity on the the L&LS, this tender-engine set of Twelve-Wheelers provided the brawn for the line, Locomotive superintendent Ingham Sutcliffe bought the two engines to handle the increase of traffic seen on the line in recent years. These were "built specially" to work the 74 3/4 miles between Londonderry and Burtonport over a line that had one four-mile stretch that climbed at 2%.
They had wide Belpaire fireboxes and were the only Irish narrow-gauge trailing a separate tender.
Retirements came in 1933 (#11) and 1954 (#12).
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 11 |
| Locobase ID | 2695 |
| Railroad | Londonderry & Lough Swilly |
| Country | Ireland |
| Whyte | 4-8-0 |
| Number in Class | 2 |
| Road Numbers | 11-12 |
| Gauge | 3' |
| Number Built | 2 |
| Builder | Hudswell, Clarke |
| Year | 1905 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 13.50 / 4.11 |
| Engine Wheelbase (ft / m) | 21.62 / 6.59 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.62 |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 15,680 / 7112 |
| Weight on Drivers (lbs / kg) | 59,136 / 26,824 |
| Engine Weight (lbs / kg) | 129,920 / 58,931 |
| Tender Loaded Weight (lbs / kg) | 47,488 / 21,540 |
| Total Engine and Tender Weight (lbs / kg) | 177,408 / 80,471 |
| Tender Water Capacity (gals / ML) | 1800 / 6.82 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 4.40 / 4 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 25 / 12.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 45 / 1143 |
| Boiler Pressure (psi / kPa) | 170 / 1170 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 15.5" x 22" / 394x559 |
| Tractive Effort (lbs / kg) | 16,972 / 7698.38 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.48 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | |
| Firebox Area (sq ft / m2) | 115.90 / 10.77 |
| Grate Area (sq ft / m2) | 15 / 1.39 |
| Evaporative Heating Surface (sq ft / m2) | 1005 / 93.37 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1005 / 93.37 |
| Evaporative Heating Surface/Cylinder Volume | 209.17 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 2550 |
| Same as above plus superheater percentage | 2550 |
| Same as above but substitute firebox area for grate area | 19,703 |
| Power L1 | 4205 |
| Power MT | 627.06 |