Class E (Locobase 140)

Data from C&NW 10 - 1952 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Many thanks to Chris Hohl for his 22 September 2017 email reporting unlikely boiler pressure values for 177 entries. A Locobase macro caused the error .) Works numbers were 53039-53044 in May 1913, 53045-53046 in June; 54516-54519 in April; 55540-55543 in January 1916, 56294-56295 in October.

This class of Omaha Road Pacifics delivered in May & June 1913, April 1914, and January & November 1916, was essentially identical to the E class engines of the Chicago & North Western (Locobase 4856), although they did have a few more fire tubes in their boilers.

Class E - late (Locobase 9383)

Data from C & NW 10 - 1952 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.(Thanks to Chris Hohl for his inquiry about the ES upgrade.)

Earlier E-class Pacifics are shown in Locobase 140. After World War I, the North Western completed this large class of engines with a purchases of 20 from Schenectady (62694-62713 in April 1921) and 20 from Dunkirk, New York's Brooks works. (Works numbers 63497-63506 in October 1922, 63883-63892 in March 1923). The basic dimensions remained the same in the firebox and the power segments (i.e., cylinder volume) remained unchanged as did piston valve diameter, which still came in at 12" (305 mm)

But there were some tweaks, particularly in the use of Young valve gear in preference to the earlier batches' Baker equipment. These saw their wheelbases grow by 1 1/2 ft (457 mm) and weight rise by several tons. In both batches, some tubes were exchanged for two more superheater flues, and boiler pressure now reached 200 psi. Still, very little notice of the USRA designs seems to have been taken. Brooks locomotives were delivered with cast-steel trailing trucks.

The entire class was converted to Walschaert valve gear some time after their delivery. Almost all were rebuilt as E-S engines in the 1940s. Locobase hasn't been able to establish exactly what features were added. The 1952 diagram book, which does not use the E-S designation, credits most of the class with a stoker, Alco power reverse gear, cross-compound air pump, and train control. The members of this class still on the roster dropped the 1 from its road number in 1951-1952, except for the 1602, which was renumbered 672.

Retirements began in 1937, but most engines served in the late 1940s and early 1950s, and the last didn't leave service until 1956.

Class E- superheated - 1580 (Locobase 15906)

Data from C & NW 1 - 1927 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Works numbers for 1580-1609 were 53032-53035 in April 1913, 53036-53038 in May, 54503-54508 in April 1914, 54509-54514 in May, 54847-54851 in September, 55534-55539 in December 1915, 56229-56234 in October 1916, 57317-57328 in September 1917.

Firebox heating surface included 27 sq ft (2.51 sq m) of arch tubes. The first batches used Walschaert gear.; see Locobase 15907. The 1909 locomotives had 23" cylinders and are shown in Locobase 15905.

Although most of the specifications were similar to the 1540 Walschaert locomotives, the newer engine had 2" (51 mm) smaller piston valves at 12" (305 mm). 1610-1627 put 164,5000 lb (74,616 kg) on the drivers and weighed, 263,500 lb (119,252 kg) ready for service.

617 and 620 were fitted in 1941 with the same air-smoothed casing as the E-4 Hudsons. On the shorter wheelbase, the design looked less powerful and speedy than stubby. The engine's gained almost 8 tons of weight, but added tractive effort when the boiler pressure was reset to 200 psi. Unlike many other streamliner modifications, however, these two did not shed the shrouds even after they were removed from the Minnesota 400 and placed in local passenger service.

Class E- superheated - to 1539 (Locobase 4856)

Data from C & NW 1 - 1927 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

The E class totalled 168 locomotives built at Schenectady from 1909 to 1923. Firebox heating surface included 27 sq ft of arch tubes. The first batches used Walschaert gear, but beginning with 1580 (delivered in May 1913), the design operated Baker valve gear.

The data shown here applied to all in the class but those produced for the North Western after World War One. For those, see Locobase 9383.

Class E-1 (Locobase 4364)

Data from reproduction of 1913 Alco Bulletin 1016 on Richard Leonard's [] (accessed 16 June 2006) and from the 1927 C & NW locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for his 30 June 2014 noting the 1916 batch from Schenectady.)

This batch operated on secondary passenger service. According to the diagram book, the class was delivered in three batches in five years. The first fifteen came in 1910 and used Walschaert valve gear. Their consecutive works numbers: 49020-49034; their road numbers, on the other hand, ranged from 56 to 941-944. The next batch, which use Baker valve gear, had road numbers 2201-2220 and were delivered in 1913-1915 with work numbers 53025, 53029-31 (April 1913), 54852-61 (Sept 1914), and 55544-55549 (November 1915). The last six--2221-2226--had works numbers 56235-56240 in September 1916.

NB: The Alco table shows the heating surface area and tube count as recorded in the specs (2,623 sq ft and 168 small tubes). The 1927 book shows 147 tubes and a 2,405 sq ft measurement. Locobase isn't sure whether the tube count would have dropped because that many were removed to simplify maintenance or because data in the 1927 book is somehow incomplete or incorrect. Other classes of locomotives showed a similar decrease, which suggests a railroad policy.

Class E-2- 1934 upgrade (Locobase 15892)

The data from a C&NW 10 - 1952 locomotive diagram (supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange) (Many thanks to Chris Hohl, whose comments relating to the E-2A and E-2B tender capacities led to a new Locobase entry covering the 1934 upgrade.

Firebox surface area included 14 sq ft (1.30 sq m) of arch tubes, 74 sq ft (6.87 sq m) of thermic syphons, and a combustion chamber. Drury (1993) notes that their dimensions place them about halfway between the two USRA classes.

The four original 1923 E-2A oil-burners described in Locobase 1184 were substantially rebuilt in 1934, adopting cast-steel cylinders, 225-psi boilers, and riding on 79" drivers. They also received blow-off mufflers and Mars R 250 oscillating headlights.

The other eight followed, but remained coal burners (E-2B). E-2As lost their boosters and converted back to coal burning and used automatic stokers beginning in December 1939 with 2907. The new tender weighed almost 20 tons more than the original coal tender.

The rest of the E-2A quartet followed suit in February 1940 (2903), November (2902), and December (2908). At that point, the whole class became E-2s once again.

They left service in 1954-1957.

Class E-2a, E-2b (Locobase 1184)

The data are taken from a C&NW 1 - 1927 locomotive diagram (supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange) showing the details of the eight-locomotive coal-burning variant of the upgrade. (Many thanks to Chris Hohl, whose comments relating to the E-2A and E-2B tender capacities led to a new Locobase entry covering the 1934 upgrade; see Locobase 15892.)

Firebox surface area included 14 sq ft (1.3 sq m) of arch tubes, 74 sq ft (6.85 sq m) of thermic syphons, and a combustion chamber. Drury (1993) noted that their dimensions place them about halfway between the two USRA Light (Locobase 172) and Heavy (Locobase 173) Pacific classes.

Hohl's comments clarify the tender capacities of the two types, which Locobase confirms with the 1927 locomotive diagrams. The tenders behind the four E-2As--2902-2903 and 2907-2908--were oil-burners carried 15,000 US gallons (56,775 litres)each.; their fuel capacity amounted to 5,000 gallons (18,925 litres). E-2B--the other two-thirds of the class-- trailed lighter tenders that held 18 tons of coal and 10,000 gallons (37,850 litres) of water.

All of the class was extensively rebuilt beginning in 1934; see Locobase 15892.

Class E-3 (Locobase 5154)

Data from

[] . See also C&NW 10 - 1952 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for pointing out an incorrect tender coal capacity Works numbers were 68516-68517 in October 1930, 68518 in November.

These were the heaviest Pacifics to be built for any railroad. They were put into service on the Omaha road.

Firebox heating surface included 14.2 sq ft (1.3 sq m) of arch tubes and 72 sq ft (6.7 sq m) of thermic syphons. Note too the superpower-like distribution of tubes and flues characteristic of the Type E superheater layout. The later diagram shows all axles fitted with Timken roller bearings.

Class E-Walschaert-23" (Locobase 15905)

Data from "Simple 4-6-2 and 2-8-0 for the Chicago & North Western", Railway and Locomotive Engineering, Volume (February 1910), p. 76. Works numbers were 46582-46591 in October 1909, 46592-46606 in November, and 47825-47839 in October 1910.

Firebox heating surface included 27 sq ft of arch tubes. The boiler and 14" (356 mm) piston valves seem a bit oversized for the cylinder volume. At least the first 25 were delivered with Cour-Castle corrugated side sheets in the firebox; see Locobase 4367 for a full description of this standard installation on the North Western.

As these were the only Es delivered with 23" diameter cylinders, both the North Western and Alco came to the same conclusion and adopted 25" cylinders beginnning with 1541.

The first batches used Walschaert gear, but beginning with 1580 (delivered in May 1913), the design operated Baker valve gear.

The North Western superheated these locomotives; see Locobase 4856.

Class E-Walschaert-25" (Locobase 15907)

Data from "Simple 4-6-2 and 2-8-0 for the Chicago & North Western", Railway and Locomotive Engineering, Volume (February 1910), p. 76. See also "4-6-2 Locomotive for the Chicago & Northwestern R R [sic]", American Engineer & Locomotive Journal, Volume 85, No 2 (February 1911), pp. 56-57.Works numbers were 47840-47844 in October 1910, 50100-50110 in June 1911, 50111-50119 in July, 50909-50923 in April 1912.

Firebox heating surface included 27 sq ft (2.51 sq m) of arch tubes. As noted in 15905, the first 40 Es had 23" (584 mm) cylinders. Apparently concluding that the large boiler and 14" (356 mm) piston valves were underemployed, Alco switched to 25" cylinders for the last five in the 1910 batch.

They also took the critical step of introducing a Schmidt-type firetube superheater. AERJ's report offered a detailed description of the Schmidt Type A version as produced by American licensee Locomotive Superheater Company. Designed to delivery 600 degree F (316 deg C), the tubes occupied more of the flues' length than heretofore: "The rear bend," wrote AERJ, " is only 24 in (610 mm) from the back flue sheet." "Somewhat nearer" than what was customary on US locomotives, the closer proximity to the fire gave a higher degree of superheat.

Given the fundamental influence of superheaters on locomotive performance world-wide, the text and illustration are worth a look.

AERJ's review of E-class success underscored the superheater's value. On 207 mile (333 km) runs from Chicago through Rockford, Ill to Elroy, Wisc, superheated locomotives proved able to stretch tender capacity to cover the 113 miles (182 km) to the usual coal stop, thus saving a stop. Chicago-Milwaukee trains used one less ton of coal over the 85 miles (137 km) between the two cities. In terms of lb/mile, this represented a reduction of 23.5 lb/mile (6.63 kg/km).

Moreover, they proved more successful making up time. According to the C&NW, saturated 23" cylinder Es could make up no more than 10-12 minutes while superheated Es never arrived at Elroy late. On one run, a train arrived 38 minutes late at Madison. The train's superheated E class ran over the ensuing 76 miles (122 km) so quickly that it arrived in Elroy on time. The kicker: Over the same distance, saturated engines couldn't make up any time at all.

Class I-2 (Locobase 9485)

Data from Angus Sinclair (ed), "Fast Passenger 4-6-2 for the C, M, St P" Railway and Locomotive Engineering, August 1903, p. 494 and from CStPMO 4 - 1900 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 27566-27570 in May 1903, 42617 in April 1907, 47047-47048 in May 1910, 47954-47955 in December.

The article reported that they were specifically designed for fast acceleration away from a station stop and that an average train load was 410 tons. The class would be the only Pacifics on the Omaha Road and were acquired in drips and drabs over the next seven years.

The class was later superheated; see Locobase 4365.

Class I-2 - superheated (Locobase 4365)

Data from Larry Bohn, author of the website members.lsol.net/mollyandmic/c385.htm and reflects this batch of Pacifics after they were superheated; see Locobase 9485 for the original, saturated configuration of this class.

By then, they had 12" piston valves and Walschaerts gear. Firebox heating surface included 23 sq ft of arch tubes.

Bohn offers the following comments about a typical I-2:

"The "Noon Train" (northbound) at Shell Lake generally indicated to everyone in town that it was time for lunch. This low angle shot taken at about driving axle height shows details that most locomotive photos don't. first, the "laceyness" of the quill spoked driving wheels, second, the springs mounted directly above the drivers, and third, the fact that the driving wheels were quartered with the right side drivers leading the left side by 90 degrees thus spreading out the 4 power strokes per revolution evenly ....All of the Omaha passenger engines had bigger driving wheels (75", or 81") than the 69" drivers of the Iron range passenger engines, and were capable of much higher speeds although the Spooner-Baronett hill made #364 work for a living. speeds in excess of 70 mph. were common on many parts of the run."

Class L (Locobase 8386)

Data from C & NW 1 - 1927 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

These were small Pacifics that almost certainly were delivered as saturated-steam locomotives; their fireboxes favored the lignite they were designed to burn. One arrived in October 1908 (works #45236), and one in September 1909 (45933). The rest came in bigger batches of 9 in September 1910 (47891-47899) and 10 in October 1910 (49010-49019).

At some point, the class received superheaters and the data show that upgrade. As modified, this design was one of the lightest 4-6-2s on the North American standard gauge

The last was retired in 1935.