Pacific Locomotive Specifications

A & V / VS & P (SRS) Class B (Locobase #6084)

The Vicksburg, Shreverport & Pacific Pacifics were confined to these three, delivered in 1919 (BLW# 51199, 51259) and 1922 (55416). Very similar to the 1914 NO & NE locomotives (see Locobase 6090), these had the same superheater area and 13" diameter piston valves, but a larger firebox. When taken up by the Illinois Central, they were renumbered 1000-1002.

A & V / VS & P (SRS) Class B (Locobase #6085)

These were the largest engines procured by the A & V, bigger even than the 2-10-2s they'd bought a few years earlier. Firebox heating surface included 62 sq ft of Nicholson syphons and steam was delivered through 14" diameter piston valves. When the IC took control of the Vicksburg Route, this class was renumbered 1310-1312.

Alabama Great Southern (SRS) Class H/H1 (Locobase #9345)

One of surprising number of Pacifics that were delivered with saturated boilers. This design had a tiny firebox, so small in fact that Locobase believes the heating surface area does not include arch tubes that likely were there. These were later superheated and some received 24" diameter cylinders.

Alaska Railroad Class 901 (Locobase #5095)

901 & 902 pulled both passenger and freight trains; 902 (works #70336) came in 1945. http://www.alaskarails.org/pix/former-loco/JK-901.html (1 Feb 2004) tells us that even though 901 (Baldwin works number 62515) was one of two locomotives involved in the only head-on collision the road ever had (on 19 October 1943), it carried on until 1952, when it was sold to FC Langreo in Spain.

Atlanta & St Andrews Bay Class 98 (Locobase #6665)

Following up on the first 31 Pacifics of similar design (Locobase 5716), these batches differed primarily in the size of the cylinders (they were delivered with 22") and installed superheating.

The A & St A B Railway ran from Dothan, Alabama to Panama City, Florida. For such a short line, it had a surprisingly large number of light Pacifics. Alco delivered 46 locomotives to the same design over an 11-year period:

Year No delivered works# road #

1911 5 50143-50147 98-102

1911 12 53892-53903 103-114

1913 6 115-120

1914 6 121-126

1920 10 61762-61271 141-150

1922 7 63260-63267 151-157

The first 10 (works #61762-61271) arrived in 1920, adding 7 more (63260-63267) in 1922.

The tender was also rated at 10 tons of coal.

Atlanta & West Point (WPR) Class P (Locobase #7319)

Although relatively small and possessing a modest amount of calculated tractive effort, this design seems to have struck a good balance between cylinder volume and boiler size. It was a light Pacific with passenger-train drivers that gave decades of good service.

Atlanta, Birmingham & Atlantic (AB&C) Class 71 (Locobase #7609)

When orginally sold to the Florida East Coast railroad, these Pacifics had saturated boilers as shown in Locobase 5716. Several years before they were sold to the AB & C, the class was superheated as shown here. (See (e.g.) the 1926 FEC Locomotive Diagram book.)

The 79 (works# 53908) was streamlined in December 1940 to head up the Dixie Flagler. Very little on the locomotive was changed, but a skyline casing was added as well as a bullet-tipped smokebox cover. Also, the tender grew considerably and now weighed 210,500 lb when loaded with 11,000 gallons of water and 18 tons of coal.

Atlantic Coast Line (ACL) Class P - superheated (Locobase #7674)

When compared to the superheated P-1-S delivered a year later (Locobase 7681), the pressure vessel in the only set of Pacifics it had purchased with saturated boilers (Locobase 7673) was quite a bit larger. As a result, superheating the design actually added overall heating surface area to the boiler. Moreover, unlike many retrofits that took the opportunity of superheating to reduce boiler pressure, the ACL maintained its P-class engines at their original settings. The result was a powerful express passenger engine.

Atlantic Coast Line (ACL) Class P (Locobase #7673)

These were the first ACL Pacifics and the last to be delivered with saturated boilers (The first 10 used Walschaert radial valve gear while the last 5 had Baker gear (by Pilliod). Later ACL 4-6-2s had shorter boiler tubes. Some were later superheated; see Locobase 7674.

Atlantic Coast Line (ACL) Class P-1-S (Locobase #7681)

P-1s were delivered by Baldwin with superheaters and piston valves, thus becoming the first of the line's Pacifics to have that valuable addition. They were passenger engines as opposed to the mixed-traffic 4-6-2s the ACL would soon purchase.

Atlantic Coast Line (ACL) Class P-2 (Locobase #7669)

This was the third class of Pacifics to run on the ACL and the variant designed to work freight trains. As with most other such designs, the ACL found them less satisfactory than other arrangements. A good factor of adhesion and a relatively large boiler probably accounted for their surviving to the end of steam.

Atlantic Coast Line (ACL) Class P-3 (Locobase #7670)

Taking the grate of the P-2 (Locobase 7669) as is, and trimming the boiler tubes and flues by two feet, then carrying it on 69" drivers, Baldwin came up with a successful mixed-traffic Pacific that served throughout the system. Like the P-2s, the P-3s had relatively generous 14"-diameter piston valves.

Atlantic Coast Line (ACL) Class P-4 (Locobase #7672)

P-4s were essentially P-3s (Locobase 7670) with more tubes and flues. Baldwin delivered 7 in 1917 and the other 20 in 1918. Like the earlier ACL Atlantics, this class had relatively generous 14"-diameter piston valves. For some reason, a few of the class (e.g., 458, 460, 463, 473, & 480) had 18-ft

Atlantic Coast Line (ACL) Class P-5-A (Locobase #1417)

This was the "light" Pacific design standardized by the government-run USRA created in World War I and built by Baldwin and Alco. Alco-Brooks and Alco-Richmond delivered these to the ACL.

Slightly modified versions were built as the P-5-B, which see.

Atlantic Coast Line (ACL) Class P-5-B (Locobase #448)

165 built by Baldwin in 1922-1926 as dual-service locomotives. J Parker Lamb (in Perfecting the American Steam Locomotive, 2003) says that this dual-purpose use was unique among US Pacific operators. The reason lies with the ACL's type of freight traffic -- typically lightweight agricultural products. Like the New York Central, moreover, much of the ACL consisted of water-level running.

Retired in 1950-1953.

Baltimore & Ohio (B&O) Class P (Locobase #5695)

Baltimore & Ohio (B&O) Class P-1 (Locobase #2884)

Most were later superheated.

Baltimore & Ohio (B&O) Class P-3 (Locobase #1247)

Had power reverse but no mechanical stokers. 10 others, 5130-5139 built by Baldwin in 1917, were virtually identical, but designated P-4. Out of service by 1952. See Sagle, 1964 for details.

Baltimore & Ohio (B&O) Class P-5 (Locobase #1249)

This was the "light" Pacific design standardized by the government-run USRA created in World War I and built by Baldwin (20) and Alco-Richmond (10). Compared to other B&O designs, these were plush engines, being fitted with power reverse, grate shakers, and coal pushers. 20 in the class later received Walschaert valve gear and redesignated P-5a. Steam pressure in all later rose to 210 psi. All had retired by 1956. See Sagle, 1964, for details.

Baltimore & Ohio (B&O) Class P-6a (Locobase #1248)

When they entered service, the P-6s had Baker valve gear. In 1932, they were fitted with Walschaert valve gear and the BP rose from 200 to 210 psi. At that point they were redesignated P-6a and the specifications describe this upgrade.

Out of service by 1949. See Sagle, 1964 for details and Staufer

Baltimore & Ohio (B&O) Class P-1d (Locobase #126)

Sagle, 1964, says these were converted from earlier Mikados by the B&O. Railway Age (11 July 1931) published the data in this entry, but gave few details.

Baltimore & Ohio (B&O) Class P-7 (Locobase #127)

Sagle, 1964, provides details on several rebuilding programs, but in summary they were as follows:

5306 became a P-7b in 1942 when she was fitted with a B&O-designed Type R superheater; see Locobase 9380.

Four engines -- 5305, 5308-5309, 5318 -- were rebuilt as P-7c in 1944-45; see Locobase 9381.

Similar rebuilds were wrought on several more P-7s. In 1946, four streamlined P-7d -- 5301-5304 -- were assigned to the Cincinnatian. These and the P-7e -- 5312, 5314-5317, 5319 -- also had the new frames of the P-7c. In addition, all axles were fitted with roller bearings. Four different firebox designs appeared on the P-7e: 5314 had the simplest rework, gaining thermic syphons and 2 arch tubes; 5315 got a syphon, 5 arch tubes, and a combustion chamber; 5317 had Nicholson circulators; and 5312, 5316, and 5319 received the semi-watertube fireboxes fitted to the 5309 and 5318.

The last P-7 retired in 1958.

Baltimore & Ohio (B&O) Class P-7B (Locobase #9380)

5306 was delivered in 1927 as part of the 20-locomotive P-7 class produced by Baldwin (Locobase 127). It became a P-7b in 1942 when it was fitted with a B&O-designed Type R superheater. The specifications above show the locomotive after it was equipped with a semi-watertube boiler that subdivided heating surface into 293 sq ft for the sheets, 135 sq ft in arch tubes, 57 sq ft in troughs, and 51 sq ft in side tubes.

Baltimore & Ohio (B&O) Class P-7c (Locobase #9381)

These four engines -- 5305, 5308-5309, 5318 -- had their boilers remounted on solid-steel engine beds with integrally cast cylinders. Other changes included feedwater heaters, a front-deck shield around several pumps and pipes, and a lowered headlight. Firebox heating surface then included 14 sq ft of arch tubes and 70 sq ft of thermic syphons.

Two of the four -- 5309 and 5318 -- were fitted with semi-watertube fireboxes that provided a total of 429 sq ft of heatings surface. Both engine and tender trucks received roller bearings in 1951.

Bangor & Aroostook Class F (Locobase #6615)

Curiously, the diagram notes the type of superheater and the number of flues, but not the area. Locobase estimates the area as 660 sq ft based on other superheater installations on similar locomotives.

Bessemer & Lake Erie Class P1A (Locobase #9034)

Firebox heating surface area included 21 sq ft in arch tubes.

Alco produced these locomotives in pairs, the first with slightly more exhaust clearance than the second (3/16" vs 1/8") but less valve lap (7/8" vs 1 1/16"). All four had generous 14" piston valves.

Like the earlier Eight-wheelers, the P1As constituted a very small part of the B & LE's motive power roster. They were medium-sized, medium-powered Pacifics that could easily handle the locals that ran up and down the mainline until the end of steam in 1953.

Big Four (NYC) Class K/Kb/Kf/Kh/Kk (Locobase #9406)

Based on the New York Central's K class of saturated Pacifics, this string of K classes for the Cleveland, Cincinnati, Chicago & St Louis was produced first in December 1905 as similar engines. Class K consisted of 10 Brooks-built engines with road numbers 6400-6409 and 10 more Kb followed in June 1906 as 6410-6419. After a three-year break, Schenectady built 5 Kf in July 1909 and 6 Kh in March 1910 and 4 Kh in April 1911; this brought the road number series up to 6434. Kk - 10 engines - completed the class in June 1912.

The data for the class varied slightly from sub-type to sub-type, chiefly in the number of small tubes. The specs refer to the Kk batch, which were delivered as superheated locomotives.

Bismarck, Washburn & Great Falls (Soo) Class H (Locobase #9390)

The North Dakota railroad that bought this lone Baldwin (works #23711, produced in February 1904) served the capitol and surrounding communities. It began as the Bismarck, Washburn & Fort Buford in 1898, but soon extended its lines to the lignite mines of Wilton, which produced 1,000 tons of lignite per day (making it the largest lignite mine in the world) and boasted 400 miners in 1915 and were a significant source of revenue.

The Minneapolis, St Paul & Sault Ste Marie bought the railroad in 1904 and acquired this dainty Pacific (and a very similar 2-8-2 Vauclain Compound). It is one of the smallest standard-gauge 4-6-2s to have run in North America. The low axle loading suggests that the builder was supplying as many axles as he could to run on what must have been pretty light rail.

Boston & Maine Class P-1a/b (Locobase #129)

The twelve P-1s were the B & M's first Pacifics.

P-1 3600-3606) was built by Alco in 1910; engine weight was 236,700 lb.

P-1b (3607-3611)

As the specifications suggest, these were typical, not remarkable passenger engines. Bruce Heald, in his Boston & Maine Locomotives (Arcadia Publishing, 2002), p 80, quotes Harry Frye from the latter's Minuteman Steam: "Though faithful performers, they were, for the most part, unexceptional engines and were referred to by some as the Budd cars of the steam era."

(Budd cars were Rail-Diesel Cars (RDC) with diesel engines under the center of the frame that were used for years for local passenger service. Locobase remembers his ride in a Budd car with a leaky exhaust manifold - killer ride, dude!)

After a couple of years, Alco supplied what would be the most numerous B & M Pacific; see Locobase 6630.

Boston & Maine Class P-2b/c/d (Locobase #6630)

The P-2 was an enlargement of the P-1 (See Locobase 129). Its boiler had 10 more fire tubes and each tube and flue was a foot longer. When the P-2 was introduced, firebox heating surface included 29.5 sq ft of arch tubes. A later reworking removed one of the arch tubes, but added 62.5 sq ft of thermic syphon. Otherwise, P-2s were essentially identical.

Boston & Maine Class P-3a (Locobase #130)

Enlarged P-2s with larger cylinders and 10 tons more adhesion weight, but smaller boilers. 10 built in 1923; retired in 1952-1955.

Boston & Maine Class P-4 (Locobase #131)

The National Park Service's Steamtown collection's Special History Study on the P-4a 3713 notes that it and its sisters were designed to run easily at 70 mph and travel 125 miles on a tenderful of water and 250 miles on coal. The study highlights the starring role these Pacifics played in the B & M's regional passenger service between such cities as Boston and Bangor (Maine), Worcester and Portland (Maine), Springfield (Mass) and White River Junction (Vt), and White River Junction and Troy (NY).

According to the NPS study: When the Boston and Maine took delivery of its second order of Lima Pacifics in 1937 [these would be the last 4-6-2s Lima would build for anybody], it sponsored a contest among New England schoolchildren to name those 10 engines and 10 other passenger engines. The contest was open to any pupil in any community along the railroad and included students from kindergarten to the final year of junior high school. to the locomotive a plate with the name of the boy or girl who suggested the name, as well as the name of his or her school. The contest elicited more than 10,000 names for the 20 engines.

P-4a 3710 Peter Cooper

P-4a 3711 Allagash

P-4a 3712 East Wind

P-4a 3713 The Constitution

P-4a 3714 Greylock

P-4b 3715 Kwasind

P-4b 3716 Rogers' Rangers

P-4b 3717 Old North Bridge

P-4b 3718 Ye Salem Witch

P-4b 3719 Camel's Hump

3710-3714 were P-4a and delivered in 1934; 3715-3719 were P-4b and arrived in 1937.

Described by Drury (1993) as "a quantum leap." Retired in 1953-1954.

Buffalo, Rochester, & Pittsburgh (B & O) Class WW (Locobase #2063)

Sturdy, conventional Pacifics with extended piston rods, 14" piston valves, and, as Drury (1993) notes, an "undersized trailing truck frame" that in a photo looks toylike. The firebox heating surface included 27 sq ft of arch tubes.

These lasted until 1953 in B&O service, where they were reclassed P-17/P-17a/P-18/P-18a and renumbered 5140-5148, 5185-5192. Sagle 1964.

Buffalo, Rochester, & Pittsburgh (B & O) Class WW-2 (Locobase #2065)

Smaller, lighter Pacifics that rounded out the BR&P's heavily used passenger stud. Drury (1993, 433) has a typical 1930 schedule.

In B&O service, they were P-19 (5260-5264) and lasted until 1953. Sagle 1964.

Canadian Government (CNR) Class K-1-a/b/c (Locobase #8070)

These were relatively small Pacifics that began delivery in 1905 as saturated-steam locomotives. The CLC supplied the first 11 in 1905 (works #652-662). For some reason, a six-year gap separated the second CLC batch from the first. Locobase 8071 shows that the CGR bought Montreal Locomotive Works near-sisters in that time. The CLC delivered its latter batch in 1911 (1019-1021 and 1032-1033). Beginning in 1923, they were rebuilt with superheaters and Walschaert gear.

Canadian Government (CNR) Class K-1-d/e (Locobase #8071)

Continuing the procurement of light Pacifics begun with a small order from CLC in 1905 (see Locobase 8071), the CGR ordered all 26 of its Montreal-built engines of the same design in the interim between the two CLC batches. 1906 saw 15 K-1-d produced in a batch (works #38901-38915) followed by 10 more K-1-e in 1908 (44556-44565) and the last one in 1910 (47666). Like the CLC engines, these went into service as saturated-steam locomotives, being rebuilt later with superheaters and, in some cases, Walschaert gear. The heavier variant -- K-1-e -- is shown in the specs.

Canadian Government (CNR) Class K-2-a (Locobase #8072)

These were the first of the big Pacifics that the CGR began acquiring in the teens. Montreal's works # ran 53851-53854. Although the grate was relatively generous, the firerbox heating surface was relatively stingy at about 5.9% of the evaporative heating surface total. This would be remedied to some extent in the next two batches; see Locobase 8073.

Canadian Government (CNR) Class K-2-b/c (Locobase #8073)

A year after the CGR introduced its large Pacific design (Locobase 8072), the two major Canadian builders supplied locomotives of the same tractive effort but a different balance between boiler and firebox. Montreal's batch came first (54759-54763) in 1914 with CLC contributing 5 more (1335-1339) two years later. In the K-2-b & c, the boiler had the same superheater, but fewer boiler tubes and its firebox grew with the addition of some arch tubes. Much later, the Canadian National fitted removed the arch tubes and added 65 sq ft of thermic syphons.

Canadian National (CNR) Class J-4-a / J-4b (Locobase #8068)

Starting this numerous class of small Pacifics were 5 from Montreal (works #54764-54768) in 1914. Canadian Locomotive Corporation followed with 5 more (works #1340-1344) two years later. Some of these had their fireboxes reconfigured with thermic syphons instead of arch tubes; they then possessed 266 sq ft of direct heating surface.

See Locobase 132 for the J-4e/f classes.

Like all of the J-4s, these useful 4-6-2s lasted to the end of steam on the CNR.

Canadian National (CNR) Class J-7a/b/c (Locobase #5087)

The NPS study comments that this locomotive design was very similar to the USRA Pacifics built in the same period, adding "...this locomotive was typical of 4-6-2s that operated all over North America in the 1920s through 1950s. They served on both main lines and branch lines, and though generally considered passenger train locomotives, they occasionally pulled freight."

Canadian National (CNR) Class J-4e/f (Locobase #132)

Although coming into service 6 years after the first J-4s (Locobase 8068), these engines were not substantially different. Their boilers had 8 more tubes and the firebox heating surface grew by 52 sq ft. And, as usually happens, they had put on weight. Like the others, they ran on the CNR until the end of steam.

Canadian National (CNR) Class K-4-b (Locobase #6650)

The first K-4s came from Alco (see Locobase 4362). These Baldwins (works 61073-61075) were delivered 5 years later. They had Coffin feedwater heaters and thermic syphons.

Canadian Northern (CNR) Class J-1-a (Locobase #2737)

Works numbers were 52255 to 52257.

NB: Data from reproduction of 1913 Alco Bulletin 1016 on Richard Leonard's http://www.railarchive.net/alcopacifics/index.html (accessed 16 June 2006) show identical tube & flue counts as well as the same length over tube sheets, but the result is a smaller superheater surface - 590 sq ft -- and more evaporative heating surface -- 2,478 sq ft, including the same 180 sq ft of firebox as shown in the CN diagrams.

Canadian Pacific Class G1 (Locobase #4519)

A relatively small batch of tall-drivered Pacifics built over an 8-year period by the Canadian Pacific and the Montreal Locomotive Works.

The boiler had a coned second course and the steam dome on the first course. As delivered, the class was fitted with the 22-element Vaughan-Horsey superheater, which is very similar in basic design to the much-better-known Schmidt smoke-tube design. The data in the specifications reflect that installation.

At a later date, the CPR replaced the Vaughan-Horsey superheater with the more widely used Schmidt Type A in many of its early Pacifics. Locobase 4518, although it describes the G2a, has data exactly the same as the G1 after the change.

Canadian Pacific Class G3a/G3b/G3c (Locobase #2738)

First in a series of big, powerful Pacifics. The figure for number of engines in the class covers all versions of the G3.

A National Park Service Steamtown special history study on its G3c gives details on how these came to be produced:"William H. Winterrowd had become chief mechanical officer of the Canadian Pacific Railway (CPR) in April 1918 as the World War was winding down." The study describes the other types of locomotives Winterrowd developed, then notes:

"For passenger service, CPR needed heavier locomotives because "heavyweight" six-wheel truck all-steel cars had rapidly replaced the older, lighter wooden passenger cars on main line runs. Building on Vaughan's successful G-l and G-2 Pacifics manufactured well before the World War, Winterrowd's team produced plans for four G-3-a 4-6-2s with 75-inch drive wheels for service over relatively flat terrain and five G-4-a Pacifics with smaller 70-inch drivers for main line service in hilly terrain. Numbered 2300 through 2303, one of the G-3-a locomotives appeared in July 1919 and the other three in August."

This seems to be one of the locomotives to which James Partington, Estimating Engineer for Alco, compared his company's #50000 in a 5 November 1921 Railway Age article. It's certainly a very close match, although Partington's weights (181,500 lb on the drivers, 299,000 lb total engine weight) are much lower.

Canadian Pacific Class G4a/G4b (Locobase #4522)

Compared to the earlier G1s and G2s, this small class of medium-drivered Pacifics had much larger boilers. Because the cylinder volume increased as well, the boiler proportions and performance were approximately the same as the earlier design. This satisfactory design carried on until 1954-1965.

Canadian Pacific Class G2 - Schmidt Type A (Locobase #4518)

Locobase divides this class into two variants depending on the superheater that was added to the design some time after they were put in service in 1906-1914. This entry applies to those upgraded with the Schmidt Type A superheater. Unlike the upgraded Ten-wheelers, most Schmidt engines retained their 200-psi setting. Firebox heating surface for both versions included 24 sq ft of arch tubes.

Other sub-classes (likely a few in each) offered combinations such as 21 1/4"-diameter pistons and 225-psi boiler, 20"-diameter pistons and a 250-psi boiler, and in some cases, retention of the original 21"-diameter piston and 200-psi boiler. By the diagram book's 1947 publication date, all G2s then in service had been converted to the Schmidt superheater variant.

For the Vaughan-Horsey variant, see Locobase 6556.

Similar in most respects to the G1s of the same span (1906-1914), this much larger class had 70" drivers. They were supplied by Alco-Schenectady, Canadian Pacific shops, and Montreal Loco Works and stayed in service until 1940-1961.

Canadian Pacific Class G2 - Vaughan-Horsey (Locobase #6556)

Locobase divides this class into two variants depending on the superheater that was added to the design some time after they were put in service in 1906-1914. This entry applies to those upgraded with the Vaughan-Horsey superheater and retained the 21"-diameter pistons; some V & H upgrades also adopted the 22 1/2" piston diameter, and increased the superheater flue diameter to 5 1/4". For the Schmidt Type A variant, see Locobase 4518. Firebox heating surface for both versions included 24 sq ft of arch tubes.

Similar in most respects to the G1s of the same span (1906-1914), this much larger class had 70" drivers. They were supplied by Alco-Schenectady, Canadian Pacific shops, and Montreal Loco Works and stayed in service until 1940-1961.

Canadian Pacific Class G3d (Locobase #133)

Also had 28 2" tubes.

G-3d firebox had combustion chamber . A nickel-steel boiler allowed considerably higher boiler pressure and a reduction in the number of fire tubes. On balance, there was less total heating surface, but more of it was superheated.

3e, f, g, & h were later series with much more superheat surface; see Locobases 5049 and 134.

Canadian Pacific Class G3e/G3f (Locobase #5049)

These were the first of the "superpower" G3s with smaller cylinder diameter, higher BP, and a Type E superheater that resulted in a much higher percentage of dry steam. The firebox had 33 sq ft of thermic syphons.

G3e 2351-2365 works #1944-1958 October-November 1938

G3f 2366-2377 1970-1981 April-June 1940

Data taken from specifications published by CLC in 1945 and reproduced in http://www.trainweb.org/oldtimetrains/altloco.html (consulted in May 2002). The table depicts the G3e, as indicated by a reference to a 1938 order; G3fs were identical except for slightly higher weights.. A later sub-class is described on Locobase 134.

Canadian Pacific Class G3g/G3h/G3j (Locobase #134)

Last G3 variant and the design that was produced in the greatest numbers. A shorter, obviously less crowded boiler had 14 fewer small tubes and 27 flues that were 1/2" larger in diameter.

G3g 2378- 2417 CLC works #1982-2021 January 1942 - February 1943

G3h 2418-2462 CLC 2126-2170 August 1944 - April 1945

G3j 2463-3427 MLW 76116-76125 June 1948

This design pulled not only passenger, but also freight trains.

Canadian Pacific Class G5 (Locobase #135)

"They proved as fast and as efficient as they were handsome," says OS Nock (RWC VI, pl 33), " and 'saw steam out' on many secondary lines of the CPR."

A February 1954 article in Trains magazine by FH Howard, reproduced on http://www.trainweb.org/oldtimetrains/destinedtodie.html (consulted in May 2002), agreed and provided many details on the class. Howard noted that the 1944 design had "scores of improvements", most notably a front-end throttle, roller bearings on the leading engine truck, and a Signal Foam Meter. Housing the throttle in the front allowed use of a dry pipe with slots along the underside, an arrangement "used", according to Howard, "for some years on this railroad instead of a steam dome".

Under the firebox was "probably the simplest trailing truck ever devised: not a truck at all, but an axle carried in the rigid frame with overwide pedestals set at a backward angle so when the axle moved laterally on curves, the journals were displaced longitudinally, giving truck action"

After successful trials in the East (1201) and West (1200), Montreal Locomotive Works delivered 30 G-5bs with mechanical stokers and Elesco exhaust steam injectors. 1946 saw 20 more from MLW and 20 from CLC and 1948 closed out the class with 30 from Canadian Loco.

(See Locobase 2413 for the very similar New South Wales C38. The two classes were designed separately for two very different railways, yet they have a striking resemblance)

Carolina, Clinchfield & Ohio Class P-1 (Locobase #3089)

These were the first Pacifics on the Clinchfield (more formally the Carolina, Clinchfield, and Ohio). The P-1s had inside valves and outside valve gear, an extended smokebox, spread domes with the bell between, and coned second course to the boiler. They served until 1951.

Carolina, Clinchfield & Ohio Class P-2 (Locobase #1322)

As might be expected on a mountain-profiled coal railroad, these passenger-type Pacifics (works #41679-41680) also pulled fast freights. They followed an earlier group of three that had smaller cylinders. Railway Age (November 1914) characterized the hilly terrain over which they had to operated and said that passenger engines in such service "must have capacity to maintain a high drawbar pull for sustained periods, rather than the ability to run at unusually high speeds." This meant high tractive effort and a boiler big enough to supply steam even for long periods of late-cutoff operation. Note the relatively generous superheat and the relatively high cross-sectional area of the tubes and flues compared to the grate area (the A/S ratio).

No complaints here; the engines ran until 1953.

Central of Georgia Class P-1 (Locobase #7938)

The Central of Georgia's 1927 locomotive diagram book, supplied in May 2005 by Allen Stanley from his extensive collection, shows the superheated upgrade (Locobase 4227). Most received 12" piston valves.

Central of Georgia Class P-2 - BLW (Locobase #4228)

Although Drury (1993) comments that despite the higher weight these engines were still light Pacifics, they had much bigger grates and larger cylinders (and superheaters when delivered) than the P-1s they joined on the C of Ga. 10 came from Baldwin in 1912, 4 more from Lima in 1916.

Most ran to the end of steam in the early 1950s, although at least one engine was scrapped in 1935. (Likely a casualty of some accident ...)

Central of Georgia Class P-2 - Lima (Locobase #6677)

It's interesting to see what a difference a couple of years and a switch of builders can mean to a basic layout. Locobase 4228 shows the Baldwins from 1910. The Limas in the current entry are grouped in that class, but the grate area is considerably larger.

According to the later editions of Central of Georgia books, the earlier Baldwins were later modified to the dimensions shown in this entry. By this time, firebox heating surface included 13.3 sq ft of arch tubes and 53 sq ft of syphons.

Most ran to the end of steam in the early 1950s.

Central of Georgia Class P-1 - superheated (Locobase #4227)

When the C of Ga superheated its slide-valve, Stephenson-motion Pacifics (Locobase 7938), they transacted the usual trade-off between boiler tubes and superheater flues. Unlike many such Pacific overhauls, the resulting heating surface total dropped considerably because of the small diameter of the boiler. Most received 12" piston valves.

Central RR of New Jersey Class G-1 (Locobase #6722)

These were the first Pacifics for the CNJ and they set the tone for all that followed. Note the large grate area, which shows 9-ft-wide Wootten firebox. The 1944 book shows several variations of firebox heating surface. In addition to the 198.2 sq ft of the firebox and the 66.9 sq ft afforded by the combustion chamber, other areas included:

Locomotive Syphons area Arch tubes area

820-821 3 91 3 23.3

(this is the variant in the specfications).

823 2 73.5 3 23.3

822, 824, 825 6 46

The 822's configuration matched that of the G-2s.

The engines stayed in service until the end of steam, their retirements coming in 1948-1954.

Central RR of New Jersey Class G-2 (Locobase #3307)

The first 11 Pacifics built for the CNJ were identical except that the last 6 -- the G-2 class -- had Delta trailing trucks. Unlike the G-1, which had several firebox configurations, the 1944 book shows only one for the G-2. Total firebox heating surface included 66.9 sq ft of combustion chamber and 46 sq ft in 6 arch tubes.

Central RR of New Jersey Class G-3 (Locobase #138)

Narrow (for soft coal) firebox had combustion chamber with heating surface of 64 sq ft, 113 sq ft of thermic syphons and arch tubes, boiler fitted with feedwater heater. Operated in New Jersey.

Three were painted blue to match the railroad's Blue Comet varnish in 1929. Later reclassified P47. Retired in 1950-1955.

Central RR of New Jersey Class G-4s (Locobase #139)

Later reclassified P52 and retired in 1954-1955.

Central Vermont (CNR) Class K-3b (Locobase #7097)

The CV didn't have much call for Pacifics, so this trio did the job for the railroad for 40 years until the end of steam.

Chesapeake & Ohio (C & O) Class F-15 - 1902 (Locobase #136)

First of a prolific line. These had no superheaters, Stephenson link motion, and a classic late 19th-Century profile. Among the first "Pacifics" to be built in the US. See Locobase

7605 for the as-delivered superheated version.

According to the C&O 9-1936 diagram books supplied in May 2005 by Allen Stanley from his extensive collection, those saturated engines that were superheated varied in the number of tubes and flues installed . 430's boiler held 149 2 1/4" tubes and 26 5 1/2" flues while 431 had 168 tubes and 30 flues. Almost all of the rest had 166 2 1/4" tubes and 30 5 1/2" flues. New-built F-15s with superheaters installed had 183 2" tubes.

Chesapeake & Ohio (C & O) Class F-15 - 1911 (Locobase #7605)

In Locobase 136, one of the earliest examples of this long line of C & O Pacifics appears in its saturated version. By the end of the run in 1911, Richmond was delivering the class with superheaters installed. An observer can note the tradeoffs between evaporative heating surface and superheater area. The builder took the unusual approach of reducing the diameter of the individual small tubes from 2 1/4" to 2", but adding 5 1/2" flues instead of the more usual (for the time) 5 3/8". As usual in that period, superheating meant a reduction of boiler pressure, too.

It was a design modification that changed little else. Inside Stephenson link motion still actuated the valves, the firebox heating surface retained its 23 sq ft of arch tubes, and the grate area remained unaltered as well.

F-15s were later (1915-1924) rebuilt with superheaters, mechanical stokers, Walschaerts valve gear, new cylinders, and sometimes new frames. Saw steam out on the Chessie.

Chesapeake & Ohio (C & O) Class F-16 (Locobase #6489)

According to Huddleston, "From their construction in 1913 to their scrappings in 1951-1952, the F-16s served well." At first they hauled flatland expresses trains, later taking the Charlottesville-Newport News and Ashland-Louisville sections. Over the years, the locomotives were fitted with automatic stokers.

After World War II, the class entered what Huddleston describes as heavy-duty local service such as the daily Ashland-Elkhorn run and the Columbus-Toledo "accommodation train."

Chesapeake & Ohio (C & O) Class F-17 (Locobase #3075)

In addition to the Schmidt superheater, these engines had a Ragonnet power reverse gear, Locomotive Stoker Company type C, Street mechanical stoker and Franklin pneumatic grate shaker. Firebox heating surface includes 27.4 sq ft of arch tubes.

In the 1930s, their driver diameter was increased to 74". The boiler pressure seems low; all the dimensions -- including 16" piston valves -- suggest a design capable of even more power. See Locobase 9104.

Chesapeake & Ohio (C & O) Class F-18A (Locobase #7857)

The F-18 took the final form of the C & O Pacific that's better known as its slightly younger F-19s. In the early 1930s, the class was rebuilt as F-18A.

Chesapeake & Ohio (C & O) Class F-19 (Locobase #137)

Boiler had feedwater heater, piston valves measured 14" in diameter (less than those of the F-17). The omega of C & O Pacifics, they entered service with 12,000-gallon, 15-ton coal tenders, but were later fitted with the enormous vessels shown in the specs. Also, the all in the class were fitted with roller bearings on the engine trucks; most used SKF, 494 rolled on Timkens.

Chesapeake & Ohio (C & O) Class F-17A (Locobase #9104)

Locobase 3075 describes this Richmond-built sextet as they first saw service rolling on 69" drivers. In the mid-1930s, the C & O rebuilt the engines with 74" drivers to enhance their usefulness on heavy passenger trains. Although the boiler layout remained essentially the same and still had the 4 arch tubes contributing 29 sq ft to firebox heating surface area, boiler pressure increased to 200 psi and the vessel now contained a Worthington feedwater heater; steam was still admitted to the cylinders by large 16" piston valves. Wheelbase grew by almost a foot, adhesion weight by almost 8 tons and engine weight by almost 11 tons. The loaded tender itself, which rolled on 6 axles, weighed 150 tons and would later grow to 347,000l lb as it held 18,000 gallons of water and 28 tons of coal.

Chicago & Alton Class I-1 (Locobase #9045)

This was an early Pacific that can nicely illustrate the difference between an Atlantic and a Pacific. Locobase 4096 shows the 1901 E-1 4-4-2s. Compared to that set of Atlantics, the I-1 had a nearly identical firebox, cylinders only 2" greater in diameter (and supplied through similar 12" piston valves), but tubes lengthened by 4 ft (and their number increased by about 2 dozen), and an extra axle of adhesion.

This same locomotive would be superheated; see Locobase 9046.

Chicago & Alton Class I-2 (Locobase #9047)

In the same month that Baldwin built the 73"-drivered I-1 (Locobase 9045), it also produced this express passenger version. The grate remained the same size, as did the cylinders (with their 12" piston valves), but the boiler contained 50 fewer tubes.

The I-2 was superheated; see Locobase 9048.

Chicago & Alton Class P (Harriman)/I-3 (Locobase #5313)

Drury (1993) says these were Harriman Pacifics. They entered service with Stephenson gear and inside-bearing trailing trucks, but were later fitted with outside Walschaerts valve gear and outside-bearing trucks.

Chicago & Alton Class I-4 (Locobase #4199)

It's odd that the adoption of the Pacific layout didn't lead to a wider grate. (Drury - 1993 - comments on the narrow firebox, but ascribes 22"cylinders to this batch, which the RAG clearly shows had 23" pistons.)

RAG's equivocal prediction was"...these are high-powered machines for passenger service, and as the design has been worked out in light of experience with locomotives built some time ago, the performance should be satisfactory."

These were later redesignated P-13a, and superheated; see Locobase 9050.

Chicago & Alton Class I-5 - 80"" drivers (Locobase #9052)

These were the first five locomotives of a 15-engine order from Brooks. They had the tallest drivers of any Alton class, 14" piston valves, and the Harriman-Pacific size grate. See Locobase 9054 for the superheated variant.

Chicago & Alton Class I-5 - 77"" drivers (Locobase #9051)

These were the first five locomotives of a 15-engine order from Brooks. They had the tallest drivers of any Alton class, 14" piston valves, and the Harriman-Pacific size grate. See Locobase 9051 for the 77"-drivered variant.

Chicago & Alton Class I-6 / P-16 (Locobase #7584)

These Harriman Pacifics were the equivalent of the Southern Pacific's P-6 class. Drury (1993) notes the tapered boiler course that joined the extended firebox to the front course. Although they were delivered as long ago as 1913, this decade of locomotives was the last new passenger power the Alton would buy. Drury notes that a 1943-1944 upgrade included a new superheater, Nicholson thermic syphons, and Worthington feedwater heaters.

Chicago & Alton Class I-3 - superheated / P-12 (Locobase #9049)

In superheating the Harriman Pacifics (Locobase 5313), the Alton installed its standard 28-element superheater assembly that included a reduction in tube count as well as individual tube diameter. Because the Harriman's had smaller boilers to begin with, the result was a high degree of superheat that undoubtedly increased their power.

Chicago & Alton Class I-4A - small grate / P-13 (Locobase #9050)

The superheated I-4 Pacifics retained the narrow firebox they had when originally delivered as saturated-steam engines. A later update would remove the boiler with the small grate and replace it with the one used by the I-5 engines. Even in 1930, however, 2 of the 5 -- 605 & 609 -- would still be using the narrow grate.

Chicago & Alton Class I-1 - superheated / P-10 (Locobase #9046)

Both early Pacifics underwent a superheating makeover that confined itself to redoing the boiler; this entry refers to the 73" diameter variant. The usual subtraction from the total tube number in favor of flues occurred, but was accompanied by an unusual reduction in tube diameter at the same time. The firebox now showed 29.7 sq ft of arch tubes as contributing to firebox heating surface. The engine still had its 12" piston valves.

Chicago & Alton Class I-2 - superheated / P-11 (Locobase #9048)

Although the saturated version of this design was quite different from the I-1 (Locobase 9045), the superheated conversion resulted in a locomotive whose only differences were the taller drivers and a greater adhesion weight.

Chicago & Alton Class I-5A - 77"" / P-15 (Locobase #9053)

The two sub-variants of the I-5 class went into service as saturated steam locomotives; see Locobases 9051-9052.

When the Alton's 4-6-2s were superheated, the I-5s remained divided into two subgroups based on driver diameter. They were otherwise identical except for a 5,500-lb difference in adhesion weight in favor of the 77"-driver engines shown here.

This class had some free-steaming qualities inherent in a relatively large boiler and 14" piston valves, but the Harriman Standard grate area may have prevented a full exploitation of a decent amount of superheat.

Chicago & Alton Class I-5A - 80"" / P-14 (Locobase #9054)

See Locobase 9053 for comments on the superheating of this HCS design.

Chicago & Eastern Illinois (C & EI) Class K-1 (Locobase #7168)

The first C & EI Pacifics, these came to the railroad already superheated. Steam admission came through 13" piston valves. Note the low steam pressure, which probably reflects the then-prevailing view that one of the benefits of superheating was the opportunity to reduce boiler pressure and thus lower maintenance costs.

Steam pressure was later raised and the tube-flue ratio changed; see Locobase 7174

Chicago & Eastern Illinois (C & EI) Class K-2 (Locobase #7169)

Now that Baldwin had delivered the first Pacifics to the C & EI, the company enlarged the design. The new engines had 10 more flues, which allowed an increase in the percentage of superheated heating surface despite the overall growth of the boiler. The firebox grew and now included 28 sq ft of fire tubes in its heating surface. The railroad later raised the boiler pressure in these locomotives to 200 psi.

1008 was streamlined in 1940 to head up the Dixie Flagler, but this involved only cosmetic additions.

Chicago & Eastern Illinois (C & EI) Class K-2 - 1016 (Locobase #7175)

Locobase doesn't know if the last two K-2s were delivered with a 180-psi boiler pressure like the others, but takes the opportunity offered by a different builder to show the effects of raising the BP to 200 psi.

Chicago & Eastern Illinois (C & EI) Class K-3 (Locobase #7173)

After World War I, the C & EI turned to a new builder for its last new passenger engines. In Lima they found an energetic interest in power at speed. This meant large heating surfaces, a generous grate, and a high percentage of superheat area.

Chicago & Eastern Illinois (C & EI) Class K-1a (Locobase #7174)

The original design of the K-1 Pacific showed some tentativeness. Boiler pressure was low, the firebox a b