Lancashire & Yorkshire 4-4-2 Locomotives in Great_Britain

Class Details by Steve Llanso of Sweat House Media

Class Highflyers (Locobase 3023)

Data from C J Bowen Cooke, British Locomotives: Their History, Construction, and Modern Developments (3rd rev and enlarged ed), (London: Whittaker and Co, 1900). See also Edward Cecil Poultney, British Express Locomotive Development (London: George Allen and Unwin, 1952), p. 51-53.

Coming just a year after Ivatt's pioneering Atlantics, these engines, designed by Sir John Aspinall, represented a big jump in size and power. The high-pitched boiler ahead of a Belpaire firebox was the largest then in use in Britain.

Locomotive Superintendent Hoy wrote Bowen Cooke about the design (pp. 266-: "The engines were designed to work the heavy and fast summer traffic, without 'piloting', between Manchester, Blackpool, Southport, Liverpool, Leeds, and York, over gradients of 1 in 63, 1 in 77, etc ...The dimensions represent the extreme limits of height and width available on British railways, as the engine only clears the loading gauge by a very few inches." Indeed, Poultney argues that the very tall drivers contributed to the locomotives' success. "For fast traffic, there is no doubt whatever that slide valve engines required large driving wheels for free running, while, when climbing, the relatively low speeds in revolutions would tend to improve the mean pressure developed in the cylinders for any given cut off."

Aspinall's Atlantics stayed in service long enough to gain a superheater and replace the inside bearings on the trailing axle (which tended to overheat) with outside bearings. The last of these wasn't retired until the early 1930s.

See Ahrons (1927) and Glover (1967).

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID3023
RailroadLancashire & Yorkshire
CountryGreat Britain
Number in Class40
Road Numbers1400
Number Built40
Valve GearJoy
Locomotive Length and Weight
Driver Wheelbase (ft / m) 7.29 / 2.22
Engine Wheelbase (ft / m)27.75 / 8.46
Ratio of driving wheelbase to overall engine wheelbase 0.26
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)39,200 / 17,781
Weight on Drivers (lbs / kg)78,400 / 35,562
Engine Weight (lbs / kg)131,600 / 59,693
Tender Loaded Weight (lbs / kg)68,684 / 31,155
Total Engine and Tender Weight (lbs / kg)200,284 / 90,848
Tender Water Capacity (gals / ML)2750 / 10.42
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 5.50 / 5
Minimum weight of rail (calculated) (lb/yd / kg/m)65 / 32.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)87 / 2210
Boiler Pressure (psi / kPa)180 / 12.40
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x660
Tractive Effort (lbs / kg)16,506 / 7487.00
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.75
Heating Ability
Tubes (number - dia) (in / mm)239 - 2" / 51
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)15 / 4.57
Firebox Area (sq ft / m2)175.80 / 16.34
Grate Area (sq ft / m2)26.05 / 2.42
Evaporative Heating Surface (sq ft / m2)2053 / 190.80
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2053 / 190.80
Evaporative Heating Surface/Cylinder Volume240.62
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation4689
Same as above plus superheater percentage4689
Same as above but substitute firebox area for grate area31,644
Power L18969
Power MT504.42

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