Class E6 on the

Pennsylvania Railroad The Pennsylvania Railroad (reporting mark PRR), legal name The Pennsylvania Railroad Company also known as the "Pennsy", was an American Class I railroad that was established in 1846 and headquartered in Philadelphia, Pennsylvania. It was named ...

was the final type of 4-4-2 "Atlantic"

locomotive A locomotive or engine is a rail transport vehicle that provides the Power (physics), motive power for a train. If a locomotive is capable of carrying a payload, it is usually rather referred to as a multiple unit, Motor coach (rail), motor ...

built by the railroad, and second only to the

Milwaukee Road The Chicago, Milwaukee, St. Paul and Pacific Railroad (CMStP&P), often referred to as the "Milwaukee Road" , was a Class I railroad that operated in the Midwestern United States, Midwest and Pacific Northwest, Northwest of the United States fr ...

's streamlined class A in size, speed and power. Although quickly ceding top-flight trains to the larger

K4s The Pennsylvania Railroad (PRR) K4 4-6-2 "Pacific" (425 built 1914–1928, PRR Altoona, Baldwin) was its premier passenger-hauling steam locomotive from 1914 through the end of steam on the PRR in 1957. Attempts were made to replace the ...

Pacifics, the E6 remained a popular locomotive on lesser services and some lasted to the end of steam on the PRR. One, #460, called the Lindbergh Engine, is preserved at the Railroad Museum of Pennsylvania. It was moved indoors to begin preparations for restoration on March 17, 2010. On January 10, 2011, PRR #460 was moved to the museum's restoration shop for a two- to three-year project, estimated to cost $350,000. The engine is listed in the National Register of Historic Places. "New life for old iron," January 11, 2011, Intelligencer Journal/New Era, Lancaster, PA

Design

The E6 was designed by the Pennsy's General Superintendent of Motive Power, Lines East,

Alfred W. Gibbs Alfred Wolcott Gibbs (October 27, 1856 – May 19, 1922) was a mechanical engineer in the railroad industry who attained the position of chief mechanical engineer of the Pennsylvania Railroad. He was instrumental in the design of a number of importa ...

, and his team. They produced an Atlantic of modern design, featuring a large and free-steaming boiler, outside

Walschaert valve gear The Walschaerts valve gear is a type of valve gear used to regulate the flow of steam to the pistons in steam locomotives, invented by Belgian railway engineer Egide Walschaerts in 1844. The gear is sometimes named without the final "s", since it ...

piston valves Piston valves are one form of valve used to control the flow of steam within a steam engine or locomotive. They control the admission of steam into the cylinders and its subsequent exhausting, enabling a locomotive to move under its own power ...

on the cylinders, and a cast steel KW pattern trailing truck designed by the PRR's Chief Mechanical Engineer, William F. Kiesel, Jr. Modern features never present on the E6 design, and never retrofitted, included the mechanical stoker, power reverse and feedwater heater.

Prototypes and testing

A single prototype E6 locomotive, #5075, was turned out by the PRR's Juniata Shops in 1910; as in the railroad's normal fashion, it would embark on a lengthy process of testing and experimentation before a production order was placed. By 1910, the larger

4-6-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of four leading wheels on two axles, six powered and coupled driving wheels on three axles and two trailing wheels on one axle. The locomotiv ...

"Pacific" type was the accepted express passenger locomotive, and it was somewhat contrarian for the PRR to be considering a new Atlantic class for that service. The E6, however, proved Gibbs et al. correct. The boiler proved free-steaming enough to enlarge the cylinders not once but twice; the stroke remained , but the bore began at and was enlarged to and finally to after superheating. In road testing on the Fort Wayne Division, the E6 averaged start to stop for 105 miles with a nine-car train, as well as with a thirteen-car train and with a fifteen-car train. At speeds over , the E6 equaled or bettered a K29 Pacific. This was with the original cylinder bore.

Superheating In thermodynamics, superheating (sometimes referred to as boiling retardation, or boiling delay) is the phenomenon in which a liquid is heated to a temperature higher than its boiling point, without boiling. This is a so-called ''metastable state ...

was applied after these tests, and proved itself so well that all other locomotives in the class were built superheated as class E6s, including two further prototypes. On the PRR's static test plant at

Altoona Works Altoona Works (also known as Altoona Terminal) is a large railroad industrial complex in Altoona, Pennsylvania. It was built between 1850 and 1925 by the Pennsylvania Railroad (PRR), to supply the railroad with locomotives, railroad cars and relat ...

, the final version of the E6s produced in its cylinders at 56 mph. Also tested on prototype #1092 (classified E6sa), were rotary valves designed by O. W. Young, actuated by regular Walschaerts gear. These proved successful but insufficiently so to be chosen for production locomotives over the reliable piston valve. The broad-boilered E-6 was the first locomotive to achieve over 1,000 hp per driving axle.

Production and service

Following the successful testing of the prototype locomotives, the PRR ordered a production run of a further eighty locomotives which were delivered in 1914. All were fitted with superheaters. They were largely assigned to main line limiteds between

Jersey City Jersey City is the second-most populous city in the U.S. state of New Jersey, after Newark.Manhattan Transfer and either Washington, D.C. or

Harrisburg, Pennsylvania Harrisburg is the capital city of the Commonwealth of Pennsylvania, United States, and the county seat of Dauphin County. With a population of 50,135 as of the 2021 census, Harrisburg is the 9th largest city and 15th largest municipality in Pe ...

, although they sometimes ran through to Altoona, Pennsylvania. Larger locomotives were generally used on the mountain grades past Altoona. All locomotives were fitted with boxy oil-fired headlights from new, and the production locomotives had long tailrods projecting from the front of the cylinders. The tailrods were soon removed, as they were on other PRR classes that had them, and the oil headlights were replaced by electric units and turbogenerators, the latter sited between the headlamp and the stack. As K4s Pacifics became available in greater numbers in the 1920s, the E6s locomotives were displaced from top-flight trains, but continued in service in lesser assignments, and particularly along the New Jersey seashore routes. Nine locomotives were transferred to the rosters of the Pennsylvania-Reading Seashore Lines, and including those, all 83 of class E6s were still in service in 1947. Some locomotives were leased by the PRR to subsidiary

Long Island Rail Road The Long Island Rail Road , often abbreviated as the LIRR, is a commuter rail system in the southeastern part of the U.S. state of New York (state), New York, stretching from Manhattan to the eastern tip of Suffolk County, New York, Suffolk Co ...

Lindbergh run

Celebrated pioneer aviator Charles Lindbergh returned to the United States on June 11, 1927, after his successful solo transatlantic flight from New York City to Paris; he was greeted by President

Calvin Coolidge Calvin Coolidge (born John Calvin Coolidge Jr.; ; July 4, 1872January 5, 1933) was the 30th president of the United States from 1923 to 1929. Born in Vermont, Coolidge was a History of the Republican Party (United States), Republican lawyer ...

at Washington, DC and awarded the Distinguished Flying Cross. There was intense competition between several newsreel companies to be the first to get footage of the ceremony back to New York to show in the Broadway theaters. Several companies chartered aircraft, but the International News Reel Corporation instead chartered a special train from the Pennsylvania Railroad, repeating what it had done for President Coolidge's inauguration. A plane could get from Washington to New York faster than a train, but the train could carry a darkroom to develop the film ''en route'', making the train competitive. PRR management seized the opportunity to make headlines and set everything up for a record run. Other trains would be moved out of the way of the Lindbergh newsreel special. E6s Atlantic #460 was selected, being recently overhauled but having had time to "run in" after the work; B60B baggage car #7874 was equipped as a darkroom and P70 coach #3301 would carry PRR and newsreel company officials. The crew were cleared to run as fast as they considered safe; the tender would not need refueling during the run and the water scoop would pick up water from track pans without stopping. However, the scoop was damaged during the first pickup attempt due to the speed at which the train had been traveling. An unscheduled three-minute stop near Wilmington was needed to repair it and fill up from a standpipe. The train made it to the electric changeover at Manhattan Transfer with an average speed of , a record never beaten by steam on that journey, with a reported maximum speed of , but there is no evidence to support the claim. The newsreels brought by train reached the cinema screens over an hour before the ones flown due to the delay to process the latter. The Pennsylvania Railroad used this victory extensively in publicity in the following years. Due to its historical importance, the "Lindbergh Engine" #460, was selected for preservation as a static exhibit. #460 was added to the National Register of Historic Places in 1979 as Passenger Locomotive No. 460. It was retired from service in 1955.

References

{{PRR locomotives Steam locomotives of the United States 4-4-2 locomotives E6 Passenger locomotives Railway locomotives introduced in 1910 Standard gauge locomotives of the United States