London & South Western 4-4-0 Locomotives in Great_Britain


Class Details by Steve Llanso of Sweat House Media

Class 135 (Locobase 10572)

Data from "The History of the London & South Western Locomotives," The Locomotive Magazine, Vol XII (15 June 1906), p.89. Works numbers were 1948-1959.

These were the first of William Adams's express passenger engines and were successful as far as their relatively small size would allow. As the trains grew heavier, the class was moved to short passenger service within the central district of the railway, but could be called upon to run boat trains from Southampton and daily service from Portsmouth.

Later batches with slightly less heating surface but higher boiler pressure are shown in Locobase 3006.


Class 318 (Locobase 10516)

Data from "The History of the London & South Western Locomotives," The Locomotive Magazine, Vol XI (15 July 1905), p.119. Works numbers were 1354-1359.

This design of tank engine showed a mixture of contemporary practice and some old-fashioned looking components. Among the latter were a small-wheelbase bogie and inclined cylinders and the dome well forward. The drivers looked huge and had slender spokes that conveyed a certain grace under the long, solid block of tank.


Class 348 (Locobase 3536)

Data from Ahrons (1927) and some data from the Scientific American Supplement, No. 458, October 11, 1884, which is reproduced by Project Gutenberg at ftp://sailor.gutenberg.lib.md.us/gutenberg/1/1/6/4/11647/11647-8.txt, accessed 25 January 2007. See also "The History of the London & South Western Locomotives," The Locomotive Magazine, Vol XII (15 March 1906), p.41. Works numbers were 2657-2676

Unsuccessful bogie express engines designed by WG Beattie. In addition to piston valves that had a defect that trapped water and broke and bent spindles, the cylinders were too big for the boiler and steamed badly. The LM report described a particularly mortifying moment as 348 pulled the 2:50 PM Portmouth-London express on 4 November 1890 down the Haslemere Bank. The locomotive broke both side rods, the flailing fragments tearing up splashers, boiler casing, the cab - it must have been an exciting moment.

Those that were not rebuilt by Adams with smaller cylinders were scrapped after only a dozen years in service.


Class 380 (Locobase 10571)

Data from "The History of the London & South Western Locomotives," The Locomotive Magazine, Vol XII (15 August 1906), p 133. Works numbers were 1854-1865

The tender-engine counterparts to the bogie tanks delivered to the L & SWR in 1879 (Locobase 10558) were these dozen mixed-traffic engines. They had careers of varied service, first working the heavy excursion trains, later hauling goods and coal trains on transfer between Brent and the Battersea Yard, and finally on local trains on the Devon and Cornwall lines in the West of England.


Class 445 (Locobase 3006)

Data from "The History of the London & South Western Railway Locomotives", The Locomotive [Magazine], Volume 13 (15 June 1907), p. 101. See also E L Ahrons, The British Railway Locomotive, 1825-1925 (London: Locomotive Publishing Company, 1926); and Glover (1967). Works numbers were 2535-2546 in 1883.

Following on from the 135s, the newer engines pressed their boilers to a setting 20 psi higher than the 1880 engines.

Several of this class (447-449, 451, 455) were refitted in 1894-1896 with new boilers measuring 52" in diameter and possessing deeper fireboxes. Heating surface area changed little although the new fireboxes' grate area dropped to 17 sq ft.(1.58 sq m).


Class 460 (Locobase 13304)

Data from "The History of the London & South Western Railway Locomotives", The Locomotive [Magazine], Volume 13 (14 September 1907), p. 157. See also "Four-Wheel Coupled Express Passenger Locomotive:London & South Westernn Railway", Engineering, Volume 44 (30 December 1887), pp. 675.

Robert Stephenson delivered 10 (works 2561-2570, 2650 and Neilson 10 (works numbers 3190-3199, road numbers 460-469), also in 1884. Stephenson delivered 1 more for the Jubilee Exhibition of 1887, works number 2650.

These differed from the 445s described in Locobase 3006 in having 79" drivers. The 1887 was originally numbered 457, but renumbered 526 before delivery to the L & SW; as the Engineering article shows, it had slightly different heating surface areas.


Class C8 (Locobase 9671)

Data from "New Locomotive Types of 1897," The Railway World, 7 April 1898, p. 120 and from C J Bowen Cooke, British Locomotives: Their History, Construction, and Modern Developments (3rd rev and enlarged ed), (London: Whittaker and Co, 1900)), pp. and Vaughn Pendred, The Railway Locomotive: What it is and why it is what it is, Published by D. Van Nostrand Co., 1908.

(See Locobase 9962 for the single 4-cylinder member of this class.)

Often described as a failure in later years, the so-called "water tube" firebox installed by Dugald Drummond in these Eight-wheelers anticipated in many ways the circulators and thermic syphons of a later day. Drummond adopted an idea patented by W S Smith of the Midland to increase the power of express locomotives when an enlargement of the boiler was not possible because of loading-gauge restrictions.

Angus Sinclair, writing in the June 1901 edition of his Railway and Locomotive Engineering Journal, p. 255-256 gives the clearest description of the layout. In the deep firebox, Drummond placed two "nests" of water tubes, the front nest of 36 (six rows of 6) sloping to the right (as seen from the footplate), the rear next of 25 (top three rows of 6, one row of 5, and one of 4) sloping to the left. Each tube measured 2 1/2" in outside diameter and 3 ft 7" long and was rolled into the side of the firebox in the same way as were the firetubes to the tubesheet.

Sinclair and Bowen Cooke both noted the more than doubling of direct heating surface that resulted from this installation. Vaughn Pendred would write glowingly about the performance of such fireboxes in 1908: "The endurance of the Drummond tubes seems to be almost phenomenal. Their average life is eight years and two months and their average mileage is 306,992. After 200,000 miles they are clean inside and as good as new, and this although they are exposed to the highest temperature in the fire-box, which nearly approaches that of a steel melting furnace."

Yet the overall verdict was that the design was unsuccessful, in all likelihood because of the maintenance burden of servicing 61 water-filled tubes that were subjected to a temperature range of almost 2000 degrees. However adverse the experience might have proven, Nicholson's development of the thermic syphon slightly more than ten years later suggests that the Drummond idea was sound in concept, if overdone in practice.

Another set built with a conventional firebox are shown in Locobase 2259; these were the renowned T9 Greyhounds..


Class D15 (Locobase 2284)

Data from Ahrons (1927) and O S Nock, Railways in the Years of Pre-Emininence, 1905-1919 (Blandford Press, 1971), plate 45. See also [link], citing Forge, Eric E. Eastleigh and locomotive design v 1. 342-7.

These Dugald Drummond engines had steam dryers (not quite superheaters) and larger boilers than earlier L&SW 4-4-0s. OS Nock says that their performance improved when a conventional superheater replaced the steam drier; see Locobase 3129.

Steamindex pronounced the design "brilliant" and quotes Eric Forge's description of Drummond's "masterpiece": ". "Here was a large enough boiler, allied to large cylinders, inside the frames with piston valves and Walschaerts gear, and what was more important, outside admission valves."


Class D15 - superheat (Locobase 3129)

Data from "Converted Superheater 4-4-0 Express Engine, L& SWR", Locomotive Magazine, Volume XXI [21] (15 June 1915), p. 122.

When the Drummond engines were superheated by R W Urie, these were the dimensions they then sported. Urie installed his Eastleigh design in the smokebox. The tender retained a feed water heater consisting of 65 water tubes 18 ft (5.49 m) long and measuring 1 1/4" in diameter; heating surface area was calculated as 382 sq ft (35.49 sq m).

OS Nock (RWC IV, pl 36) says that their performance improved when a conventional superheater replaced the steam drier.

As noted in the earlier entry, D15s ran for more than 40 years, most of that time in very useful secondary line service.


Class L12 Bulldogs (Locobase 2281)

Data from Ahrons (1927), supplemented by A T Taylor, Modern British Locomotives (London: E & FN Spon, Ltd, 1907), p. 10

Although designed by Dugald Drummond, these engines appear to be repeats (or at least very near kin) of the earlier Adams engines on the L&SW. Ahrons gives the firebox heating surface as shown. It seems awfully high, especially when compared to other British 8-wheelers of the time. Yet other Drummond engines on the L&SW had similar values. The answer lies in the watertubes, which added 165 sq ft (15.3 sq m) of heating surface to the 163 sq ft (15.1 sq m)of the firebox walls.


Class T3 (Locobase 2251)

Data from A E Kyffin, "Standard South Western Locomotives", Railway World, Volume 5, No 3 (March 1897) and E L Ahrons, The British Railway Locomotive, 1825-1925 (London: Locomotive Publishing Company, 1926). See also "LSWR Adams T3 class 4-4-0" on the Southern Railway E-Mail Group website at [link], last accessed 9 June 2022.

Designed by William Adams. OS Nock (RWC II, pl 115) says the key to the success of this outside-cylinder design lies in "extreme simplicity in design, sound engineering principles and superb workmanship in construction." They had a healthy ratio of boiler tube cross-section to grate area. Nock notes that they were fast engines, too, frequently topping 75 mph (121 kph).

Kiffin observed that as good as the 580s (Locobase 2250) had proven to be, "the gradients in some parts of the system are so severe and the loads so heavy, that it was found necessary to design an even more powerful class of express engine."

He included some examples of what South Western passenger trains might expect to meet: The grades, "particularly between Salisbury and Exeter, are fearfully heavy and long, varying from 1 in 70 (1.4%) to 1 in 100 (1%) and from1 to 5 miles (1.6 to 8 km) in length.

The slightly later X6 (657-666) were similar.

The X2s of the same year are similar engines with taller drivers; see X2 (Locobase 2250).


Class T6 (Locobase 5972)

Data from J. Pearson Pattison, British Railways: Their Passenger Services, ... (London: Cassell & Co, 1893), p. 84. See also "LSWR Adams X2/T6 Class 4-4-0" on the Southern Railway E-Mail Group website at [link], last accessed 9 June 2022. Production deliveries included 677 in September 1895, 678 in October, 679 in November, 680-682 in December, 683-684 in March 1896 and 685-686 in May.

Designed by William Adams. Pattison commented that the outside cylinders on the T6s, as on most L&SW passenger engines, "would seem to have been the rule on this line almost from the earliest date. (The line's goods engines placed their cylinders inside the frame.). Ten more X6 locomotives rolled on 79" (2,007 mm) drivers, but were other similar.

T6s were the last of the 4-4-0 series that began with the T3 (85" drivers-see Locobase 2251) and X2 (79" drivers; see Locobase 2250) . SEMG's account calls them "very successful locomotives ... at least on a par with, and in many cases better than, contemporary locomotives of other lines." Suspension design and equalizing beams played a significant part minimizing " the tendency for outside cylinder locomotives to be unsteady." Its value combined with their long wheelbase "did in fact lead to very smooth running."

SEMG adds "When the equalizing beams were removed later in their lives the running was considerably impaired."


Class T9 Greyhound - Urie H (Locobase 20916)

Data from "Superheated 4-4-0 Express Locomotive, L&SW Railway," Locomotive Magazine, Volume XXVIII [28] (15 August 1922), pp. 220-221

R W Urie eyed the large class of Drummond-designed T9 Greyhounds (Locobase 2259) and determined to superheat them; his first two locomotives appeared in April (314) and (304) in July 1922.. He approached the upgrade conservatively, keeping most of the components that were not directly affected by the addition of a superheater. Slide valves located inside the frame supplied the Joy valve gear, the grate remained unchanged as was the firebox--although the 61 sq ft of cross-box water tubes were deleted.

Although superheating area seems on the small side, Urie found enough improvement in tractive effort to apply the modifications to the entire class from 1922-1928 (718 was the last of the few 1928 upgrades to complete in September.).

Only eleven of the class wouldn't be assigned a British Railways number in 1948. All of the others carried on at least into the 1950s and 1960s.

Only 30120 evaded the ferro-knacker's cutters. Restored while in the National Railway Museum's care, it ran on the Mid Hants Railway from May 1983 until its boiler certificate expired. Loaned to the Bluebell Railway as a static display beginning 24 March 1994, the 120 was transferred to the Bodmin & Wenford Railway on 1 February 2008. Their Flour Mill Workshop restored the engine to full operating condition.

After a head-on collision in July 2017, the 30120 ws sent to the Swanage Railway where it was repaired and put back in service. A continuing concern was corrosion in the ylinder blocks, which are located directly below the smokebox. Even though the engine's boiler failed its steam test in July 2020, the NRM and Swanage Railway agreed to store it while preparing for limited disassembly to assess the boiler. Swanage Railway Trust reported it was "keen to complete this as soon as possible so that it can be included in [the SRT's] overall motive power plan."


Class T9 Greyhounds (Locobase 2259)

Data from Ahrons (1927), which refer to the set of 30 built by Dubs & company that had 165 sq ft of water tubes crossed in their fireboxes in addition. The 1907 Catalogue of Mechanical Engineering Collection in the Science Division of the Victoria & Albert Museum (Board of Education South Kensington)., p 104. says that at least some were built by Dubs & Company.

Designed by Adams. Southern Railway historians writing on the [link] website (3 April 2004) say these "Greyhounds" were probably Dugald Drummond's most successful London and South Western designs. They accelerated quickly (thus the nickname) and were "remarkably free-running with a well steaming [sic] boiler, substantial firegrate and masterfully applied Stephenson link motion."

(Ahrons says Joy valve gear.)


Class X2 (Locobase 2250)

Data from "Four-Wheels-Coupled-Bogie Express Passenger Engine for the London and South Western Railway. '580' Class", Railway Engineer, Volume 12, No 4 (April 1891), pp. 85. See also "Four-Wheels-Coupled-Bogie Express Passenger Engine for the London and South Western Railway. '580' Class", Railway Engineer, Volume 12, No 4 (April 1891), pp. 85; and "LSWR Adams X2/T6 Class 4-4-0" on the Southern Railway E-Mail Group website at [link], last accessed 9 June 2022.

Designed by William Adams as part of a series of 60 outside-cylinder express passenger engines; the other 30 are described under T3 (Locobase 2251). The T6 (677-686) were similar to the X2s.

Hollingsworth (1982) notes that these engines hit 80 mph (129 kph) on many occasions, "a reflection on the excellent riding qualities of the Adams own celebrated design of bogies, which gave the drivers the confidence to run at these speeds." Photos show that the smokebox end of the boiler was located above the outside cylinders. The center of the leading bogie and rested on a long, low, sloping plinth that extended forward practically to the buffer beam. The tall drivers had coupled splashers with smaller fairings over the upper half of the crank orbit.

Kiffin observed that an effort to simplify production, the GER used cast steel for wheels, bogie castings, crossheads, piston, and horn blocks and "the axles also are of special cast steel."

C J Bowen Cooke, "British Locomotives", (London: Whitaker & Co, 1894) gave more specifics about their performances on non-stop services, which can be shown in a table:

Departure Name From To Miles Speed

12.30 p.m. Bournemouth express Waterloo Southampton 79 1/4 47.55 Southampton Vauxhall 78 50

2.15 p.m. Waterloo Christchurch 104 46

11.00 a.m Waterloo Salisbury 83 1/2 43.5

3.00 p.m. Waterloo Basingstoke 48 48.

"These runs," Cooke comments,"have very often to be accomplished with loads of as much as ten six-wheeled vehicles weighing 15 tons each, and four bogie carriages of about 20 tons each, giving a gross train load (including engine and tender) of about 310 tons."

See T3 for OS Nock's comments on the soundness of the design.

Principal Dimensions by Steve Llanso of Middle Run Media
Class135318348380445
Locobase ID10572 10516 3536 10571 3006
RailroadLondon & South WesternLondon & South WesternLondon & South WesternLondon & South WesternLondon & South Western
CountryGreat BritainGreat BritainGreat BritainGreat BritainGreat Britain
Whyte4-4-04-4-0T4-4-04-4-04-4-0
Number in Class126201212
Road Numbers135-146318-323348-367380-391445-456
GaugeStdStdStdStdStd
Number Built126201212
BuilderBeyer, PeacockBeyer, PeacockSharp, StewartBeyer, PeacockRobert Stephenson & Co
Year18801875187618791883
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.59 8.58 / 2.629 / 2.74 8.50 / 2.59 8.50 / 2.59
Engine Wheelbase (ft / m)21.92 / 6.6820.50 / 6.2522.50 / 6.8621.71 / 6.6221.96 / 6.69
Ratio of driving wheelbase to overall engine wheelbase 0.39 0.42 0.40 0.39 0.39
Overall Wheelbase (engine & tender) (ft / m)40.33 / 12.2920.50 / 6.2510.08 / 3.0740.08 / 12.2243.47 / 13.25
Axle Loading (Maximum Weight per Axle) (lbs / kg)32,368 / 14,68230,968 / 14,04734,496 / 15,64733,600 / 15,241
Weight on Drivers (lbs / kg)64,400 / 29,21160,872 / 27,61166,680 / 30,24666,752 / 30,278
Engine Weight (lbs / kg)103,936 / 47,14599,092 / 44,94797,272 / 44,122103,208 / 46,814103,264 / 46,840
Tender Loaded Weight (lbs / kg)59,584 / 27,02754,992 / 24,94459,584 / 27,02772,240 / 32,768
Total Engine and Tender Weight (lbs / kg)163,520 / 74,172152,264 / 69,066162,792 / 73,841175,504 / 79,608
Tender Water Capacity (gals / ML)1320 / 52730 / 10.343000 / 11.363000 / 11.36
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)54 / 2751 / 25.5056 / 2856 / 28
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)79 / 200769 / 175379 / 200767 / 170285 / 2159
Boiler Pressure (psi / kPa)140 / 970120 / 830140 / 970140 / 970160 / 1100
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x61017" x 24" / 432x61018.5" x 26" / 470x66018" x 24" / 457x61018" x 24" / 457x610
Tractive Effort (lbs / kg)11,713 / 5312.9310,253 / 4650.6913,404 / 6079.9613,811 / 6264.5712,442 / 5643.60
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.50 4.54 4.83 5.37
Heating Ability
Tubes (number - dia) (in / mm)234 - 1.75" / 44212 - 1.56" / 40218 - 1.75" / 44218 - 1.75" / 44
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)10.21 / 3.11
Firebox Area (sq ft / m2)111 / 10.3296 / 8.92145.70 / 13.54101 / 9.39111.46 / 10.35
Grate Area (sq ft / m2)17.77 / 1.6517.40 / 1.6217.86 / 1.6616.96 / 1.5817.75 / 1.65
Evaporative Heating Surface (sq ft / m2)1223 / 113.66992 / 92.191035 / 96.191136 / 105.581162 / 107.95
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1223 / 113.66992 / 92.191035 / 96.191136 / 105.581162 / 107.95
Evaporative Heating Surface/Cylinder Volume173.02157.34127.95160.71164.39
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation24882088250023742840
Same as above plus superheater percentage24882088250023742840
Same as above but substitute firebox area for grate area15,54011,52020,39814,14017,834
Power L146373222401936295513
Power MT317.48291.11239.97364.16

Principal Dimensions by Steve Llanso of Middle Run Media
Class460C8D15D15 - superheatL12 Bulldogs
Locobase ID13304 9671 2284 3129 2281
RailroadLondon & South WesternLondon & South WesternLondon & South WesternLondon & South WesternLondon & South Western
CountryGreat BritainGreat BritainGreat BritainGreat BritainGreat Britain
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class2130101020
Road Numbers460-478, 147, 526702-719, 721-732463-472415
GaugeStdStdStdStdStd
Number Built21301020
BuilderseveralDubs & CoNine ElmsNine ElmsNine Elms
Year18841898191219121904
Valve GearStephensonJoyWalschaertWalschaertJoy
Locomotive Length and Weight
Driver Wheelbase (ft / m) 8.50 / 2.5911 / 3.3510 / 3.0510 / 3.0510 / 3.05
Engine Wheelbase (ft / m)21.96 / 6.6923.25 / 7.0925.25 / 7.7025.25 / 7.7023.25 / 7.09
Ratio of driving wheelbase to overall engine wheelbase 0.39 0.47 0.40 0.40 0.43
Overall Wheelbase (engine & tender) (ft / m)46.83 / 14.2749.5847.83 / 14.58
Axle Loading (Maximum Weight per Axle) (lbs / kg)34,160 / 15,49542,336 / 19,20342,784 / 19,407
Weight on Drivers (lbs / kg)66,752 / 30,27884,448 / 38,30589,376 / 40,54083,104 / 37,695
Engine Weight (lbs / kg)102,480 / 46,484122,192 / 55,425133,840132,496120,848 / 54,816
Tender Loaded Weight (lbs / kg)64,736 / 29,36459,472 / 26,97682,208109,760100,352 / 45,519
Total Engine and Tender Weight (lbs / kg)167,216 / 75,848181,664 / 82,401216,048242,256221,200 / 100,335
Tender Water Capacity (gals / ML)3360 / 12.734200 / 15.9142004500 / 13.264800 / 18.18
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)10 / 9 4.40 / 4 4.404 / 4 4.40 / 4
Minimum weight of rail (calculated) (lb/yd / kg/m)56 / 2870 / 3574 / 3769 / 34.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)79 / 200779 / 200779 / 200779 / 200779 / 2007
Boiler Pressure (psi / kPa)160 / 1100175 / 1210200 / 1380180 / 1240175 / 1210
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x61018.5" x 26" / 470x66019.5" x 26" / 495x66020" x 26" / 508x66019" x 26" / 483x660
Tractive Effort (lbs / kg)13,387 / 6072.2516,755 / 7599.9521,275 / 9650.1920,142 / 9136.2717,673 / 8016.35
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.99 5.04 4.44 4.70
Heating Ability
Tubes (number - dia) (in / mm)218 - 1.75" / 44280 - 1.5" / 38247 - 1.75" / 0 - 1.75" / 0247 - 1.75" / 44
Flues (number - dia) (in / mm) - 5.25" / 0
Flue/Tube length (ft / m)10.21 / 3.1110.79 / 3.2912.40 / 3.7812.40 / 3.7810.79 / 3.29
Firebox Area (sq ft / m2)111.75 / 10.38394 / 36.62318144.50 / 13.43328 / 30.47
Grate Area (sq ft / m2)17.60 / 1.6427.40 / 2.5527 / 2.5127 / 2.5124 / 2.23
Evaporative Heating Surface (sq ft / m2)1163 / 108.051500 / 139.411724 / 160.221285 / 119.421550 / 144
Superheating Surface (sq ft / m2)231 / 23.42
Combined Heating Surface (sq ft / m2)1163 / 108.051500 / 139.411724 / 160.221516 / 142.841550 / 144
Evaporative Heating Surface/Cylinder Volume164.53185.44191.83135.92181.67
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation28164795540048604200
Same as above plus superheater percentage28164795540055894200
Same as above but substitute firebox area for grate area17,88068,95063,60029,91257,400
Power L151319884971010,2448615
Power MT338.92516.07505.37457.09

Principal Dimensions by Steve Llanso of Middle Run Media
ClassT3T6T9 Greyhound - Urie HT9 GreyhoundsX2
Locobase ID2251 5972 20916 2259 2250
RailroadLondon & South WesternLondon & South WesternLondon & South WesternLondon & South WesternLondon & South Western
CountryGreat BritainGreat BritainGreat BritainGreat BritainGreat Britain
Whyte4-4-04-4-04-4-04-4-04-4-0
Number in Class3010716620
Road Numbers577-578, 557-575677-686304, 314937580-599
GaugeStdStdStdStdStd
Number Built30106620
BuilderNine ElmsNine ElmsNine ElmsseveralNine Elms
Year18901896192218991890
Valve GearJoyStephensonJoyJoyStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)9 / 2.749 / 2.7410 / 3.0510 / 3.05 8.50 / 2.59
Engine Wheelbase (ft / m)23.50 / 7.1623.50 / 7.1623.25 / 7.0923.25 / 7.0923 / 7.01
Ratio of driving wheelbase to overall engine wheelbase 0.38 0.38 0.43 0.43 0.37
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)35,16835,280 / 16,15539,424 / 17,88239,76035,056 / 15,195
Weight on Drivers (lbs / kg)67,526 / 30,62976,440 / 34,67376,832 / 34,85079,296 / 35,96868,432 / 30,786
Engine Weight (lbs / kg)108,752 / 49,329107,520 / 50,802115,024 / 52,174112,896 / 51,209109,200 / 49,451
Tender Loaded Weight (lbs / kg)74,36871,680 / 33,733100,464 / 45,57091,168 / 41,35371,680 / 32,514
Total Engine and Tender Weight (lbs / kg)183,120179,200 / 84,535215,488 / 97,744204,064 / 92,562180,880 / 81,965
Tender Water Capacity (gals / ML)3960 / 15.154800 / 18.184200 / 15.914000 / 15.15
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 4.40 / 3.60 5.50 / 5 4.40 / 44 / 4
Minimum weight of rail (calculated) (lb/yd / kg/m)56 / 2864 / 3264 / 3266 / 3357 / 28.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)79 / 200785 / 215979 / 200779 / 200785 / 2159
Boiler Pressure (psi / kPa)175 / 1210175 / 1210175 / 1210175 / 1210175 / 1210
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x66019" x 26" / 483x66019" x 26" / 483x66018.5" x 26" / 470x66019" x 26" / 483x660
Tractive Effort (lbs / kg)17,673 / 8016.3516,426 / 7450.7217,673 / 8016.3516,755 / 7599.9516,426 / 7450.72
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.82 4.65 4.35 4.73 4.17
Heating Ability
Tubes (number - dia) (in / mm)230 - 1.75" / 44240 - 1.75" / 44124 - 1.75" / 44280 - 1.5" / 38240 - 1.75" / 44
Flues (number - dia) (in / mm)21 - 5.25" / 133
Flue/Tube length (ft / m)11.33 / 3.4510.75 / 3.2811.33
Firebox Area (sq ft / m2)126.40 / 11.75122.12 / 11.35142 / 13.19148 / 13.75122.10 / 11.35
Grate Area (sq ft / m2)19.75 / 1.8418 / 1.6724 / 2.2324 / 2.2319.60 / 1.82
Evaporative Heating Surface (sq ft / m2)1320 / 122.681368 / 127.091063 / 98.761500 / 139.411368 / 127.14
Superheating Surface (sq ft / m2)195 / 18.12
Combined Heating Surface (sq ft / m2)1320 / 122.681368 / 127.091258 / 116.881500 / 139.411368 / 127.14
Evaporative Heating Surface/Cylinder Volume154.71160.34124.59185.44160.34
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation34563150420042003430
Same as above plus superheater percentage34563150487242003430
Same as above but substitute firebox area for grate area22,12021,37128,82625,90021,368
Power L152725749952863815749
Power MT344.25331.62546.79354.81370.42

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