Chicago, Burlington & Quincy 2-6-2 "Prairie" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class R-1 (Locobase 2899)

Data from Corbin & Kerka (1960) and locomotive diagram published on Vernon Beck's website -- [] (accessed 22 March 2003). Some of the data comes from a 30 March 1900 Railroad Gazette article on the R class, which heralds the launch of these Burlington Prairies. See also "Notes on Prairie Type Locomotives", Railroad Gazette, Volume XXXII [32], No 42 (19 October 1900), p. 691.

Pioneered the Prairie arrangement that would represent the Burlington's principal small freight arrangement for years. Also new to the railroad was the square-topped Belpaire firebox. These engines steamed surprisingly well on the lignite fuel. In the October report, the writer spoke of "a noticeable absence of smoke" by a engine that "steamed freely at all times." Fired in the "usual way; that is, three or four shovels of coal were put in at a time ...the smoke would be brown for a few moments, but the discharge from the stack quickly cleared." In sum, there was "no doubt that the work of the fireman is materially lightened by using the short, wide grates."

Piston valve and valve gear operation was "all that could be expected." In fact, were it not for "the free movement of the reverse lever given by the piston valves it would be difficult to handle these engines in the narrow space left for the engineman between the side of the boiler and the cab." The article noted that the Baldwins then being produced would have the cabs set further back, leaving more room for the engineman.

Although they demonstrated little rolling from side to side (thanks to outside bearings on the trailing truck), the class had a "decided movement from side to side on straight track" when pulling a light train at speeds above 20 or 25 mph." Modifications to trailing truck rigging were planned.

Two of this class of 4 were rebuilt as 0-6-0 switchers. The other two were retired in the early 1930s.


Class R-2 (Locobase 814)

See also locomotive diagram published on Vernon Beck's website -- [] (accessed 22 March 2003). Also see Corbin & Kerka (1960, p 94); and DeGolyer, Volume 23, p. 200+.

60 engines -- 50 from Baldwin, 10 from the shops -- were the first large class of Burlington Prairie. These had cabs set further back on the boiler to provide more room for the crew. Seven of the Baldwins (works numbers 18794-18797, 18822-18824) were delivered to the Hannibal & St Joseph and were numbered 681-687. 40 went to the Burlington & Missouri River (18825, 18845-18848, 18867-18878, 18954-18956, 19513, 19520-19526, 19574-19577 - of these three were compounds.

Six were completed as Vauclain compounds (class R-2-C); see Locobase 16272. All were later rebuilt as G-8 0-6-0 switchers in the late 1930s.


Class R-2-C (Locobase 16272)

Data from DeGolyer, Volume 23, p. 210. Works numbers were 18951-18953 in April 1901.

Many more locomotives built to the same design were delivered as simple-expansion engines (Locobase 814). This trio (and three more for the Burlington and Missouri River) were Vauclain compounds with a single 15" (381 mm) piston valve supplying steam to the HP and LP cylinder on each side of the smokebox. The design had the distinctive square-topped Belpaire firebox whose heating surface area including 22.9 sq ft (2.13 sq m) of fire brick tubes.

All were later rebuilt as G-8 0-6-0 switchers in the late 1930s.


Class R-3 (Locobase 1040)

Data from a locomotive diagram published on Vernon Beck's website -- [] (accessed 22 March 2003) and Corbin & Kerka (1960). See also DeGolyer, Volume 24, p. 300+, and "New Six-Coupled Freight Locomotives", American Engineer and Railroad Journal, Volume 76, No. 11 (November 1902), p. 343. Works numbers 20859-20862 in August 1902; 20914-20916, 20957-20959, 20994, 21007, 21015, 21021-21023 in September 1902; 21069-21073, 21113, 21140-21142, 21152, 21160-21161, 21173 in October 1902; 21205-21208, 21222-21225, 21254-21257, 21288, 21299-21302 in November 1902; 21378-21379 in December 1902; and 21436 and 21543 in January 1903.

50 larger mixed-traffic Prairies that followed the R-2s (Locobase 814), but retained the Belpaire firebox, 12" (305 mm) piston valves, and upright cylinder arrangement. Tubes were longer than those of the R-2. Baldwin's specs showed a firebox heating surface area of 141 sq ft (13.1 sq m) and evaporative heating surface area of 3,055.5 sq ft (283.87 sq m). AERJ's report said that the trailing truck were like the earlier passenger engines in having the equalizers over rather than under the outside journals.

Retired as Prairies in 1928-1930; many converted to G-9A 0-6-0 switchers.


Class R-4 - BLW - 1904 (Locobase 1041)

Corbin & Kerka (1960); DeGolyer, Volume 27, pp. 180+ and 28, pp. 100+; CB&Q 3 -1953 diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (See also data from a locomotive diagram published on Vernon Beck's website -- [] (accessed 22 March 2003) and "Heavy Passenger Locomotive", American Engineer and Railroad Journal, Volume 78 (September 1904), pp. 356-357 (Thanks to Chris Hohl for his 1 October 2019 email reporting the original tender capacity and loaded weight.)

140 Prairies altogether, built by Baldwin (1900-1939, 2000-2049) and Brooks (1940-1989). Baldwin 24436, 24456-24459, 24463-24466; 24474, 24477-24478; 24485-24488; 24492-24497; 24505-24506; 24511-24514 in July 1904;

24528-24529, 24537-24538, 24542-24543, 24552, 24557,

24568-24569, 24601-24602, 27244-27251, 27271-27272, 27286-27290, 27305-27309, 27337, 27357-27359, 27371-27374, 27388-27390, 27403 in January 1906, 27418-27420; 27421, 27456-27459; 27495-27498; 27509-27511; 27539-27540, 27558 in February.

Throughout the R-4 and R-5 procurement, the builders were described as having been built "from the railroad company's drawings". Design replaced the R-3's Belpaire firebox (Locobase 1040) with conventional one. Contributing to the heating surface area was 31 sq ft (2.88 sq m) from arch tubes in the first seven, increasing to 37 sq ft (3.44 sq m) in succeeding engines.

Also, the cylinders canted inward (seen from in front) so that the 12-in (305 mm) piston valves were inboard of the drivers and run with inside valve gear. Moreover, some had 25" (635 mm) diameter cylinders and a lower boiler pressure of 165 psi.

Some were rebuilt with Walschaert's gear and 25" x 28" cylinders, and some were converted to 0-6-0s. Others carried on until the early 1950s.


Class R-4 - BLW - 1906 (Locobase 16540)

Corbin & Kerka (1960); DeGolyer, Volume 29, pp. 16; CB&Q 3 -1953 diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for his 1 October 2019 email reporting the original tender capacity and loaded weight.)

140 Prairies altogether, built by Baldwin and Brooks. Works numbers for this second batch were 27244-27251, 27271-27272, 27286-27290, 27305-27309, 27337, 27357-27359, 27371-27374, 27388-27390, 27403 in January 1906, 27418-27420; 27421, 27456-27459; 27495-27498; 27509-27511; 27539-27540, 27558 in February.

Throughout the R-4 and R-5 procurement, the builders were described as having been built "from the railroad company's drawings". Design replaced the R-3's Belpaire firebox (Locobase 1040) with conventional one. Also, the cylinders canted inward (seen from in front) so that the 12-in (305 mm) piston valves were inboard of the drivers and run with inside valve gear.

The 1906 batch's Baldwin specification does not mention any arch tubes for the firebox.

Four were rebuilt with superheaters.


Class R-4 - Brooks (Locobase 16541)

Data from "Prairie Type Freight & Passenger Locomotive-Chicago, Burlington & Quincy Railway", American Engineer and Railroad Journal", Volume 79, No. 3 (March 1905), pp. 78-79. Works numbers were 30396-30415 in January 1905, 30416-30445 in February.

140 Prairies altogether with 50 built by Brooks.

Throughout the R-4 and R-5 procurement, the builders were described as having been built "from the railroad company's drawings". The R-4 design replaced the R-3's Belpaire firebox (Locobase 1040) with conventional one.

Also, the cylinders canted inward (seen from in front) so that the 12-in (305 mm) piston valves were inboard of the drivers and run with inside valve gear. Brooks's locomotives had fireboxes offering 20 fewer sq ft (1.86 sq m) than those of the Baldwins (Locobase 1041), which had the same length and width. It's possible that the Brooks fireboxes were shallower or that the two builders calculated the area differently.

Like the Baldwins,Most of the Brooks locomotives served the Burlington for 25-30 years before being retired in the early 1930s. The shops converted eight of the class to G-10 0-6-0s in the late 1920s.

The Burlington sold the 1967 and 1980 to the Toledo, Peoria & Western in January 1926.


Class R-4A - Emerson (Locobase 7695)

Data from CB&Q 3 -1953 diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

1912, 1924, 1937-1938, 1948-1949, 1963, 1972, 1987-1988, 2005, 2018, 2027, 2039, 2052-2053, 2057, 2062, 2099, 2110, 2113, 2149, 2151, 2189, 2191, 2196, 2215, 2219, 2222

In rebuilding the R-4 Prairies (Locobase 1041) with superheaters, the Burlington chose to equip some with Schmidt, some with Emerson superheaters. (See Locobase 5456 for the Schmidt variant.)

The subject of the current entry is the rebuilt R-4 with an Emerson superheater. Compared to the Schmidt variant, the Emerson has fewer superheater flues and a smaller area. (R-5As with an Emerson superheater -- Locobase 7696 -- had four more 2 1/4" tubes). The firebox heating surface included 33.4 sq ft in 4 arch tubes. Also, some of the rebuilt engines retained their 22" cylinders and 200-psi pressure setting while others increased cylinder diameter to 25" and reduced the boiler pressure to 165 psi. All leading truck wheels saw their diameters decrease from 37 1/4" to 33".


Class R-4A/R-5A - Schmidt (Locobase 5456)

Data from a locomotive diagram published on Vernon Beck's website -- [] (accessed 22 March 2003). Amended by CB&Q 3 -1953 diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.)

These are the superheated rebuilds of the R-4 and R-5 Prairies (Locobases 1041, 2900, and

7697). Firebox heating surface included four arch tubes with a total of 33 sq ft (3.07 sq m). The result was three sub-types. The one in the present entry reflects a common design using the Schmidt Type A superheater. Some of these locomotives had boilers set to 200 psi and were credited with a tractive effort of 43,116 lb (19,557 kg or 191.8 kN. Later diagrams showed a pressure dropped to 185 psi.

The CB&Q's R-5 diagram lists a variety of cylinder volume-boiler pressure combinations likely to appear in both R-4 and R-5 classes:

BP Cylinder bore & stroke Tractive effort

200 psi (13.8 bar) 22 x 28 (559 x 711 mm) 33,400 lb (15,150 kg or 148.56 kN)

185 (12.8 bar) 22 x 28 30,900 (14,016 kg or 137.45 kN)

165 (11.4 bar) 22 x 28 27,600 (12,519 kg or 122.77 kN)

165 25 x 28 (635 x 711 mm) 35,600 (16,148 kg or 158.36 kN)

The other two (Locobase 7695 & 7696)-- reflecting the introduction of an Emerson superheater -- differed in size from the R-4 to the R-5.

Once converted, the class carried on in light freight work until the end of steam in some cases.


Class R-5 - BLW (Locobase 2900)

Corbin & Kerka (1960); DeGolyer, Volume 29, pp. 16+; CB&Q 3 -1953 diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (See also data from a locomotive diagram published on Vernon Beck's website -- [] (accessed 22 March 2003). Baldwin works numbers were 28396-28397, 28420-28421, 28426-28427, 28449, 28459, 28472, 28487, 28490 in June 1906; 28503-28507, 28536-28539, 28546-28547, 28569, 28580, 28590, 28595-28597, 28610, 28628, 28647, 28653, 28662, 28672, 28681-28682 in July; 28703, 28720-28723, 28754-28755, 28778-28779, 28798, 28821, 28831, 28864, 28900 in August.

175 R-5s -- 2055-2224, built by Baldwin and Alco-Brooks in 1906-1907 (Locobase 7697)-- had a only slightly larger boiler, but were otherwise similar to the R-4s (Locobase 1041). The firebox heating surface included 33.4 sq ft in 4 arch tubes.

Baldwin delivered two superheated locomotives within this batch as trial horses for the Schmidt superheater, much as they had with a single Prairie sent to the Great Northern at the same time (see Locobase 8388). Numbered 2098-2099, they had 157 small tubes and 32 5 1/2" superheater flues. Cylinder diameter increased to 25 1/4" and boiler pressure remained set at 210 psi; however, the Baldwin spec shows a tractive power estimate of 22,800 lbs. See the DeGolyer holding, Volume 29, p. 48-49.

Some rebuilt with Walschaert's gear, and some were converted to 0-6-0s. Others were superheated; see Locobase 5456.

Many were scrapped in the late 1920s-early 1930s. Others carried on until the late 1940s-early 1950s.


Class R-5 - Brooks (Locobase 7697)

Corbin & Kerka (1960); ; "Prairie-Type Freight & Passenger Locomotive-Chicago, Burlington & Quincy Railway," American Engineer and Railroad Journal, Volume 79 (March 1905), pp. 78-80; CB&Q 3 -1953 diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (See also data from a locomotive diagram published on Vernon Beck's website -- [] (accessed 22 March 2003). (Thanks to Chris Hohl for his 1 October 2019 email reporting the original tender capacities and loaded weight.)

175 R-5s -- 2055-2224, built by Baldwin and Brooks in 1906-1907 (see also Locobase 2900) were similar to the R-4s except (Locobase 1041) that this last set of 75 from Brooks had twelve more small tubes and consequently more heating surface area.

Tenders came in two versions, both weighing 154,000 lb (69,358 kg). One variant carried 16 tons (14.5 metric tons) of coal and 6,000 US gallons (22,710 litres) of water. Other traded a ton of coal for 2,000 more gallons of water as shown in the specs.

Some rebuilt with Walschaerts gear, and some were converted to 0-6-0s. Others carried on until the early 1950s.


Class R-5A - Emerson (Locobase 7696)

Data from CB&Q 3 -1953 diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

In rebuilding the R-5 Prairies (Locobases 2900 & 7697) with superheaters, the Burlington chose to equip some with Schmidt, some with Emerson superheaters. (See Locobase 5456 for the Schmidt variant.)

The subject of the current entry is the rebuilt R-5 with an Emerson superheater. Compared to the Schmidt variant, the Emerson had fewer superheater flues and a smaller area; the design had 50 sq ft (4.65 sq m) more of tube heating surface than the modified R-4 The firebox heating surface included 33.4 sq ft (3.1 sq m) in four arch tubes. Also, some of the rebuilt engines retained their 22" cylinders and 200-psi pressure setting while others increased cylinder diameter to 25" and reduced the boiler pressure to 165 psi. All leading truck wheels saw their diameters decrease from 37 1/4" to 33".

Principal Dimensions by Steve Llanso of Middle Run Media

ClassR-1R-2R-2-CR-3R-4 - BLW - 1904
Locobase ID2899 814 16272 1040 1041
RailroadChicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)
CountryUSAUSAUSAUSAUSA
Whyte2-6-22-6-22-6-22-6-22-6-2
Number in Class41035080
Road Numbers1701-17041710-17191703-17051721-1770 / 1800-18491900-1989
GaugeStdStdStdStdStd
Number Built41035080
BuilderCB&QseveralseveralBurnham, Williams & CoBurnham, Williams & Co
Year19001901190119021904
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)11.33 / 3.4512.08 / 3.6812.08 / 3.6813 / 3.9613.37 / 4.08
Engine Wheelbase (ft / m)26.25 / 828 / 8.5328.08 / 8.5628.25 / 8.6130.71 / 9.36
Ratio of driving wheelbase to overall engine wheelbase 0.43 0.43 0.43 0.46 0.44
Overall Wheelbase (engine & tender) (ft / m)51.96 / 15.8455 / 16.7655 / 16.7655.75 / 16.9962.23 / 18.97
Axle Loading (Maximum Weight per Axle) (lbs / kg)48,000 / 21,77248,000 / 21,77251,400 / 23,315
Weight on Drivers (lbs / kg)110,270 / 50,018130,550 / 59,217130,550 / 59,217134,550 / 61,031151,000 / 68,493
Engine Weight (lbs / kg)151,220 / 68,592170,000 / 77,111170,000 / 77,111181,920 / 82,518210,000 / 95,255
Tender Loaded Weight (lbs / kg)148,500 / 67,359148,500 / 67,359148,500 / 67,359120,400 / 54,613154,000 / 67,222
Total Engine and Tender Weight (lbs / kg)299,720 / 135,951318,500 / 144,470318,500 / 144,470302,320 / 137,131364,000 / 162,477
Tender Water Capacity (gals / ML)5000 / 18.946000 / 22.736000 / 22.736000 / 22.738000 / 30.30
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)9 / 812 / 1112 / 1112 / 1116 / 15
Minimum weight of rail (calculated) (lb/yd / kg/m)61 / 30.5073 / 36.5073 / 36.5075 / 37.5084 / 42
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)64 / 162664 / 162664 / 162669 / 175369 / 1753
Boiler Pressure (psi / kPa)190 / 13.10200 / 13.80200 / 13.80200 / 13.80210 / 14.50
High Pressure Cylinders (dia x stroke) (in / mm)19" x 24" / 483x61020" x 24" / 508x61016" x 24" / 406x61021" x 26" / 533x66022" x 28" / 559x711
Low Pressure Cylinders (dia x stroke) (in / mm)27" x 24" / 686x610
Tractive Effort (lbs / kg)21,863 / 9916.9025,500 / 11566.6224,157 / 10957.4428,250 / 12814.0035,058 / 15902.06
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.04 5.12 5.40 4.76 4.31
Heating Ability
Tubes (number - dia) (in / mm)194 - 2.25" / 57272 - 2.25" / 57272 - 2.25" / 57272 - 2.25" / 57301 - 2.25" / 57
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)16.09 / 4.9017.15 / 5.2317.15 / 5.2318.31 / 5.5819 / 5.79
Firebox Area (sq ft / m2)139 / 12.92178.70 / 14.04178.70 / 16.60151.10 / 14.04227 / 21.09
Grate Area (sq ft / m2)42 / 3.9042 / 3.9042 / 3.9042 / 3.9054.25 / 5.04
Evaporative Heating Surface (sq ft / m2)2076 / 192.942911 / 268.032911 / 270.443071 / 285.303581 / 332.68
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2076 / 192.942911 / 268.032911 / 270.443071 / 285.303581 / 332.68
Evaporative Heating Surface/Cylinder Volume263.45333.45521.15294.72290.67
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation798084008400840011,393
Same as above plus superheater percentage798084008400840011,393
Same as above but substitute firebox area for grate area26,41035,74035,74030,22047,670
Power L171279297510384469244
Power MT427.47471.00258.53415.17404.89

Principal Dimensions by Steve Llanso of Middle Run Media

ClassR-4 - BLW - 1906R-4 - BrooksR-4A - EmersonR-4A/R-5A - SchmidtR-5 - BLW
Locobase ID16540 16541 7695 5456 2900
RailroadChicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)
CountryUSAUSAUSAUSAUSA
Whyte2-6-22-6-22-6-22-6-22-6-2
Number in Class5050229100
Road Numbers2000-20491940-19891912, 1924, 1937-1938, 1948-1949, 19632050-2149
GaugeStdStdStdStdStd
Number Built5050100
BuilderBurnham, Williams & CoAlco-BrooksCB&QCB&QBurnham, Williams & Co
Year19061905191219121906
Valve GearStephensonStephensonWalschaertWalschaertStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)13.37 / 4.0813.37 / 4.0813.37 / 4.0813.37 / 4.0813.37 / 4.08
Engine Wheelbase (ft / m)30.71 / 9.3630.71 / 9.3630.71 / 9.3630.71 / 9.3630.70 / 9.36
Ratio of driving wheelbase to overall engine wheelbase 0.44 0.44 0.44 0.44 0.44
Overall Wheelbase (engine & tender) (ft / m)62.23 / 18.9762.23 / 18.9762.23 / 18.9762.23 / 18.9762.23 / 18.97
Axle Loading (Maximum Weight per Axle) (lbs / kg)51,400 / 23,31551,400 / 23,31551,700 / 23,451
Weight on Drivers (lbs / kg)151,000 / 68,493154,000 / 69,853151,000 / 68,493163,250 / 74,049152,000 / 68,946
Engine Weight (lbs / kg)210,000 / 95,255212,500 / 96,388210,000 / 95,255233,370 / 105,855216,000 / 97,976
Tender Loaded Weight (lbs / kg)148,200 / 67,222154,000 / 69,853148,200 / 67,222148,200 / 67,222148,200 / 67,222
Total Engine and Tender Weight (lbs / kg)358,200 / 162,477366,500 / 166,241358,200 / 162,477381,570 / 173,077364,200 / 165,198
Tender Water Capacity (gals / ML)8000 / 30.308000 / 30.308000 / 30.308000 / 30.308000 / 30.30
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)16 / 1516 / 1513 / 1213 / 1213 / 12
Minimum weight of rail (calculated) (lb/yd / kg/m)84 / 4286 / 4384 / 4291 / 45.5084 / 42
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)69 / 175369 / 175369 / 175369 / 175369 / 1753
Boiler Pressure (psi / kPa)210 / 14.50210 / 14.50165 / 11.40185 / 12.80210 / 14.50
High Pressure Cylinders (dia x stroke) (in / mm)22" x 28" / 559x71122" x 28" / 559x71125" x 28" / 635x71125" x 28" / 635x71122" x 28" / 559x711
Tractive Effort (lbs / kg)35,058 / 15902.0635,058 / 15902.0635,571 / 16134.7539,882 / 18090.1935,058 / 15902.06
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.31 4.39 4.25 4.09 4.34
Heating Ability
Tubes (number - dia) (in / mm)301 - 2.25" / 57301 - 2.25" / 57167 - 2.25" / 57158 - 2.25" / 57303 - 2.25" / 57
Flues (number - dia) (in / mm)24 - 5.5" / 14030 - 5.5" / 140
Flue/Tube length (ft / m)19 / 5.7919 / 5.7919 / 5.7919 / 5.7919 / 5.79
Firebox Area (sq ft / m2)227 / 21.09170.90 / 15.88233.40 / 21.69230 / 21.37190 / 17.65
Grate Area (sq ft / m2)54.25 / 5.0454 / 5.0254.20 / 5.0454.20 / 5.0454.20 / 5.04
Evaporative Heating Surface (sq ft / m2)3581 / 332.683514 / 326.462748 / 255.392822 / 262.173560 / 330.73
Superheating Surface (sq ft / m2)596 / 55.39682 / 63.36
Combined Heating Surface (sq ft / m2)3581 / 332.683514 / 326.463344 / 310.783504 / 325.533560 / 330.73
Evaporative Heating Surface/Cylinder Volume290.67285.23172.72177.37288.96
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation11,39311,340894310,02711,382
Same as above plus superheater percentage11,39311,34010,55311,93211,382
Same as above but substitute firebox area for grate area47,67035,88945,44350,63539,900
Power L19244856311,06713,5198841
Power MT404.89367.76484.74547.70384.69

Principal Dimensions by Steve Llanso of Middle Run Media

ClassR-5 - BrooksR-5A - Emerson
Locobase ID7697 7696
RailroadChicago, Burlington & Quincy (CB&Q)Chicago, Burlington & Quincy (CB&Q)
CountryUSAUSA
Whyte2-6-22-6-2
Number in Class75
Road Numbers2150-2224
GaugeStdStd
Number Built75
BuilderAlco-BrooksCB&Q
Year19061912
Valve GearStephensonWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)13.37 / 4.0813.37 / 4.08
Engine Wheelbase (ft / m)30.70 / 9.3630.71 / 9.36
Ratio of driving wheelbase to overall engine wheelbase 0.44 0.44
Overall Wheelbase (engine & tender) (ft / m)62.23 / 18.9762.23 / 18.97
Axle Loading (Maximum Weight per Axle) (lbs / kg)51,700 / 23,45151,700 / 23,451
Weight on Drivers (lbs / kg)152,000 / 68,946152,000 / 68,946
Engine Weight (lbs / kg)216,000 / 97,976216,000 / 97,976
Tender Loaded Weight (lbs / kg)148,200 / 67,222148,200 / 67,222
Total Engine and Tender Weight (lbs / kg)364,200 / 165,198364,200 / 165,198
Tender Water Capacity (gals / ML)8000 / 30.308000 / 30.30
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)13 / 1213 / 12
Minimum weight of rail (calculated) (lb/yd / kg/m)84 / 4284 / 42
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)69 / 175369 / 1753
Boiler Pressure (psi / kPa)210 / 14.50165 / 11.40
High Pressure Cylinders (dia x stroke) (in / mm)22" x 28" / 559x71125" x 28" / 635x711
Tractive Effort (lbs / kg)35,058 / 15902.0635,571 / 16134.75
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.34 4.27
Heating Ability
Tubes (number - dia) (in / mm)303 - 2.25" / 57171 - 2.25" / 57
Flues (number - dia) (in / mm)24 - 5.5" / 140
Flue/Tube length (ft / m)19 / 5.7919 / 5.79
Firebox Area (sq ft / m2)233 / 21.65233.40 / 21.69
Grate Area (sq ft / m2)54.20 / 5.0454.20 / 5.04
Evaporative Heating Surface (sq ft / m2)3624 / 336.802792 / 259.48
Superheating Surface (sq ft / m2)596 / 55.39
Combined Heating Surface (sq ft / m2)3624 / 336.803388 / 314.87
Evaporative Heating Surface/Cylinder Volume294.16175.49
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation11,3828943
Same as above plus superheater percentage11,38210,553
Same as above but substitute firebox area for grate area48,93045,443
Power L1938811,119
Power MT408.49483.81

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