Pennsylvania Railroad class T1

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Pennsylvania Railroad T1
Pennsylvania Railroad TR1.JPG
T1 5549 on display.
Type and origin
Power typeSteam
DesignerRalph P. Johnson [1]
Raymond Loewy [2]
Builder Altoona Works (5500–5524)
Baldwin Locomotive Works (5525–5549, 6110–6111)
Pennsylvania Railroad T1 Steam Locomotive Trust (5550) [3]
Serial numberAltoona 4560–4584
BLW 72764–72788 (5525–5519)
Build date1942 (6110–6111)
1945–46 (5500–5549)
2014–present (5550) [3]
Total produced52
Specifications
Configuration:
​
 •  Whyte 4-4-4-4
 •  UIC 2′BB2′
Gauge 4 ft 8+1⁄2 in (1,435 mm)
Leading dia. 36 in (914 mm)
Driver dia.80 in (2,032 mm)
Trailing dia. 42 in (1,067 mm)
Wheelbase 107 ft 0 in (32.61 m)
Length122 ft 9+3⁄4 in (37.43 m)
Width11 ft 1 in (3.38 m)
Height6111: 15 ft 6 in (4.72 m) [4]
Axle load 71,680 lb (32.51  t)
Adhesive weight 279,910 lb (127.0 t)
Loco weight502,200 lb (227.8 t)
Tender weightEmpty: 197,400 lb (89.54 t);
Loaded: 442,500 lb (200.7 t)
Total weight944,700 lb (428.5 t)
Tender type180 P 76 (Prototype), 180 P 84 (Production)
Fuel type Coal
Fuel capacity85,200 lb (38.65 t)
Water cap.19,200 US gal (73,000 L; 16,000 imp gal)
Firebox:​
 • Grate area92 sq ft (8.5 m2)
Boiler100 in (2,540 mm)
Boiler pressure300 lbf/in2 (2.07 MPa)
Heating surface:​
 • Firebox490 sq ft (45.5 m2)
 • Tubes and flues4,209 sq ft (391.0 m2)
 • Total surface5,639 sq ft (523.9 m2)
Superheater:
​
 • TypeType A
 • Heating area1,430 sq ft (132.9 m2)
Cylinders Four
Cylinder size 19.75 in × 26 in (502 mm × 660 mm), 18.75 in × 26 in (476 mm × 660 mm) (some)
Valve gear Franklin poppet
Valve typePoppet valves
Performance figures
Maximum speed120 mph (193 km/h)
Power output6,500 ihp (4,800 kW)
Tractive effort 64,653 lbf (287.6 kN) (85%), [5] 58,271 lbf (259.2 kN) (85%) (some)
Factor of adh. 4.33
Career
Operators Pennsylvania Railroad
Class T1
Number in class52 original, plus 1 under construction [3]
Numbers6110, 6111, 5500-5549, 5550
LocaleWestern Pennsylvania, Ohio, Indiana, Illinois
First run1942
Retired1953
Withdrawn1952–1953 [6]
Scrapped1953–1956 [6] [3]
DispositionAll 52 original scrapped, 1 new build (PRR 5550) under construction

The Pennsylvania Railroad (PRR) class T1 duplex-drive 4-4-4-4 steam locomotives, introduced in 1942 with two prototypes and later in 1945-1946 with 50 production examples, were the last steam locomotives built for the PRR and arguably its most controversial. They were ambitious, technologically sophisticated, powerful, fast and distinctively streamlined by Raymond Loewy. However, they were also prone to wheelslip both when starting and at speed, in addition to being complicated to maintain and expensive to run. [ citation needed ] The PRR decided in 1948 to place diesel locomotives on all express passenger trains, leaving unanswered questions as to whether the T1's flaws were solvable, especially taking into account that the two prototypes did not have the problems inherent to the production units.

Contents

An article appearing in a 2008 issue of the Pennsylvania Railroad Technical and Historical Society Magazine showed that inadequate training for engineers transitioning to the T1 may have led to excessive throttle applications, resulting in driver slippage. [7] Another root cause of wheelslip was faulty "spring equalization": The stiffnesses of the springs supporting the locomotive over the axles were not adjusted to properly equalize the wheel-to-track forces. [8] The drivers were equalized together but not equalized with the engine truck. In the production fleet the PRR equalized the engine truck with the front engine and the trailing truck with the rear engine, which helped to solve the wheelslip problem. [9]

Development

No. 6110, the "sister" prototype of class T1 prototype No. 6111. Its streamlined casing was designed by renowned industrial designer Raymond Loewy. Pennsylvania RR streamlined locomotive T1.jpg
No. 6110, the "sister" prototype of class T1 prototype No. 6111. Its streamlined casing was designed by renowned industrial designer Raymond Loewy.
A T1 prototype leaving Chicago's Union Station in February 1943 with the Manhattan Limited to New York PRR-T1.jpg
A T1 prototype leaving Chicago's Union Station in February 1943 with the Manhattan Limited to New York

Before the T1, the last production express passenger engine the PRR had produced was the K4s of 1914, produced until 1928. Two experimental enlarged K5 locomotives were produced in 1929, but they weren't considered enough of an improvement to be worthwhile. After that, the PRR's attention switched to electrification and the production of electric locomotives; apparently, the railroad decided that it did not need more steam locomotives.

However, the deficiencies of the K4s became more evident during the 1930s. The locomotives performed well, but as train lengths increased they proved to be underpowered; double-headed K4s locomotives became the norm on many trains. The railroad had many locomotives available, but paying two crews on two locomotives per train was expensive. Meanwhile, other railroads were leaping ahead, developing increasingly powerful passenger train locomotives. Rival New York Central built 4-6-4 Hudsons, while other roads developed passenger 4-8-2 "Mountain" type and then 4-8-4 "Northern" type designs. The PRR's steam power began to look outdated.

The PRR began to develop steam locomotives again in the mid-to-late 1930s, but with a difference. Where previous PRR locomotive policy had been conservative, new radical designs took hold. Designers from the Baldwin Locomotive Works, the PRR's longtime development partner, were eager to prove the viability of steam in the face of new competition from diesel-electric locomotives. They persuaded the railroad to adopt Baldwin's latest idea: the duplex locomotive. This split the locomotive's driving wheels into two sets, each with its own pair of cylinders and rods. Until then, the only locomotives with two sets of drivers were articulated locomotives, but the duplex used one rigid frame. In a duplex design cylinders could be smaller, and the weight of side and main rods could be drastically reduced. Given that the movement of the main rod could not be fully balanced, the duplex design would reduce the "hammer blow" on the track. The lower reciprocating mass meant that higher speeds could be achieved. Use of poppet valves also increased the speed because they gave very accurately timed delivery of steam to the cylinders. [ citation needed ] However, there was a drawback of the metallurgy used; the poppet valve could not withstand the stress of sustained high-speed operation (meaning over 100 mph (160 km/h) on production T1s). [ citation needed ]

The first PRR duplex was the single experimental S1 No. 6100 of 1939. It managed to reach 100.97 miles per hour (162.50 km/h) on level track while pulling a 1,350-ton passenger train. Its performance encouraged the PRR to continue to develop duplex steam locomotives. The S1 was built unnecessarily large for her exhibition at the 1939 New York World's Fair until October 1940; therefore, its turning radius prohibited it from operating over most of the PRR network. The 6-4-4-6 design reduced driving set traction to the point that it was especially prone to wheel slip[ citation needed ]; thus only one Class S1 was built. The PRR returned to Baldwin to develop a duplex design fit for series production.

The PRR ordered two Baldwin prototypes (Nos.  6110 and 6111) at a cost of $600,000 on June 26, 1940. [10] Both prototypes had numerous teething problems and were prone to wheelslip if not handled carefully by the engineer, but favorable test reports resulted in a production order for 50 T1s, split between the PRR's own Altoona Works and Baldwin. On December 20, 1944, the PRR Board authorized the purchase of 50 Class T1 locomotives for $14,125,000 ($282,500 per unit, equal to $4,889,546 each today). Baldwin's chief designer, Ralph P. Johnson, was responsible for the mechanical aspects of the new T1 class. [1] Designer Raymond Loewy obtained US Patent D 136,260 for an early T1 conceptual design with a high-mounted cab located over the forward driving set. [11] While that suited Baldwin's objective of making the most distinctive steam locomotive possible, practical considerations led the T1 design to be revised to the conventional cab position with a slight modification of the unique nose design included in Loewy's patent. Raymonds distinctive design of the T1 heavily influenced other engines, most notably the South Australian Railways 520 class. In late 1942 Islington Railway Workshops's chief engineer Frank Hugh Harrison saw the T1 in an american magazine whilst designing the 520 class. Frank was impressed, and the streamlining of the T1 became the basis of the design. The 520 class construction pace was then increased to come out before the T1 to avoid patent claims.

The last production T1 (no. 5549) entered service on August 27, 1946. [12] Engine no. 5539 developed 5,012 hp (3,737 kW), as tested between September 11, 1946, and September 14, 1946, by Chesapeake and Ohio Railway dynamometer car DM-1 while on loan to C&O.[ citation needed ] In 1944 no. 6110, tested on the stationary test plant in Altoona, developed 6,550 ihp (4,880 kW) in the cylinders at 85 mph (137 km/h). [13] They also regularly racked up over 8,000 miles a month. [14]

PRR T-1 6110 20160929 01 PRR T-1 Steam Locomotive.jpg
PRR T-1 6110

Due to their complexity relative to other steam locomotive designs, the T1s were difficult to maintain. Designed to run reliably at speeds of up to 100 mph (160 km/h), the T1s were so powerful that they could easily exceed their designed load and speed limitations, which in turn caused increased wear and tear, particularly to the 100-mph-limited poppet valves. They were described as "free steaming," meaning they could generally maintain boiler pressure regardless of throttle setting. They were so powerful that violent wheel slip could occur over a wide speed range if the engineer did not handle the throttle carefully; loss of driver traction at high speeds, especially when the T1 was under heavy load while ascending grades, caused damage to the poppet valves. The Franklin Type A valve gear applied to the T1s was designed for continuous speeds at 100 mph, and sprints up to 125 mph. In interviews with historian William L. Withuhn in the 1970s, Franklin engineers Julius Kirchhof and Ray Delano both claimed a Franklin technician charged with determining the cause of frequent poppet valve failures on the T1s saw them operated at speeds of up to 100-110 mph to make up time with short trains of six or seven cars, determining the speed by timing when the train passed mileposts. [15]

Fate

When the PRR Board decided to dieselize all first-class prime trains in 1948, most T1s were downgraded to haul secondary trains. Some of them were withdrawn from passenger service in 1949; all were out of service by 1952. They were scrapped between 1951 and 1956.

No. 5550

In 2014, a non-profit group known as The T1 Trust began restoring a T1 using the original plans with subtle performance improvements where necessary. [3] The T1 Trust's goal is to provide mainline excursion service. The T1 Trust's cost estimate to build T1 number 5550 is $10 million, with an expected completion date of 2030 [3] (This total has since been reduced to a bit more than $7 million, as a used PRR long haul tender has been acquired in lieu of new construction).

The construction of 5550 is also following construction and financing methods pioneered by the LNER Peppercorn Class A1 60163 Tornado project. [16] The first piece of the locomotive, the keystone-shaped number plate, was cast in April, 2014, followed by the first minor component, a driving spring link pin, in October, 2014. Major components completed as of March, 2019 include two Boxpok drivers, the prow, cab, third-course boiler and fire door. Front tube sheet construction was under way by a fabricator in St. Louis, Missouri. [17] [ needs update ]

In media

Crashes

See also

Related Research Articles

<span class="mw-page-title-main">Pennsylvania Railroad locomotive classification</span> Overview of locomotive classification on the Pennsylvania Railroad in the United States

Locomotive classification on the Pennsylvania Railroad took several forms. Early on, steam locomotives were given single-letter classes. As the 26 letters were quickly assigned, that scheme was abandoned for a more complex system. This was used for all of the PRR's steam locomotives, and — with the exception of the final type bought — all electric locomotives also used this scheme.

<span class="mw-page-title-main">Pennsylvania Railroad K4 class</span> Class of 425 American 4-6-2 locomotives

The Pennsylvania Railroad K4 was a class of 425 4-6-2 steam locomotives built between 1914 and 1928 for the PRR, where they served as the primary main line passenger steam locomotives on the entire PRR system until late 1957.

<span class="mw-page-title-main">Pennsylvania Railroad class M1</span>

The M1 was a class of steam locomotive of the Pennsylvania Railroad (PRR). It was a class of heavy mixed-traffic locomotives of the 4-8-2 "Mountain" arrangement, which uses four pairs of driving wheels with a four-wheel guiding truck in front for stability at speed and a two-wheel trailing truck to support the large firebox needed for sustained power. Although built for both passenger and freight work, they spent most of their service lives hauling heavy high-speed freight trains. Many PRR men counted the M1 class locomotives as the best steam locomotives the railroad ever owned.

<span class="mw-page-title-main">4-4-4-4</span> Duplex locomotive wheel arrangement

A 4-4-4-4 steam locomotive, in the Whyte notation for describing locomotive wheel arrangements, has a four-wheel leading truck, two sets of four driving wheels, and a four-wheel trailing truck. While it would be possible to make an articulated locomotive of this arrangement, the only 4-4-4-4s ever built were duplex locomotives—with two sets of cylinders driving two sets of driven wheels in one rigid frame, essentially a 4-8-4 with divided drive.

<span class="mw-page-title-main">Pennsylvania Railroad class S2</span> American steam turbine locomotive

The Pennsylvania Railroad's S2 class was a steam turbine locomotive designed and built in a collaborative effort by Baldwin Locomotive Works and Westinghouse Electric & Manufacturing Company, as an attempt to prolong the dominance of the steam locomotive by adapting technology that had been widely accepted in the marine industry. One was built, #6200, delivered in September 1944. The S2 was the sole example of the 6-8-6 wheel arrangement in the Whyte notation, with a six-wheel leading truck keeping the locomotive stable at speed, eight powered and coupled driving wheels, and a six-wheel trailing truck supporting the large firebox. The S2 used a direct-drive steam turbine provided by the Westinghouse Electric & Manufacturing Company, geared to the center pair of axles with the outer two axles connected by side rods; the fixed gear ratio was 18.5:1. Such design was to prevent energy loss and S2 achieved a mechanical efficiency of 97% which means only 3% of steam energy was lost within the propulsion equipment. The disadvantage of a direct-drive steam turbine was that the turbine could not operate at optimal speeds over the locomotive's entire speed range. The S2 was the largest, heaviest and fastest direct-drive turbine locomotive design ever built.

The Pennsylvania Railroad's class K5 were experimental 4-6-2 "Pacific" types, built in 1929 to see if a larger Pacific than the standard K4s was worthwhile. Two prototypes were built, #5698 at the PRR's own Altoona Works, and #5699 by the Baldwin Locomotive Works. Although classified identically, the two locomotives differed in many aspects, as detailed below. They were both fitted with a much wider boiler than the K4s, but dimensionally similar to those of the I1s 2-10-0 "Decapods". Most other dimensions were enlarged over the K4s as well; the exceptions being the 70 square feet (6.5 m2) grate area and the 80 in (2.032 m) drivers.

<span class="mw-page-title-main">Pennsylvania Railroad class S1</span> Experimental American 6-4-4-6 duplex locomotive

The PRR S1 class steam locomotive was a single experimental duplex locomotive of the Pennsylvania Railroad. It was designed to demonstrate the advantages of duplex drives espoused by Baldwin Chief Engineer Ralph P. Johnson. The S1 class was the largest rigid frame passenger steam locomotive ever built. The streamlined Art Deco styled shell of the locomotive was designed by Raymond Loewy.

The Pennsylvania Railroad's class P5 comprised 92 mixed-traffic electric locomotives constructed 1931–1935 by the PRR, Westinghouse and General Electric. Although the original intention was that they work mainly passenger trains, the success of the GG1 locomotives meant that the P5 class were mostly used on freight. A single survivor, prototype #4700, is at the National Museum of Transportation in St Louis, Missouri.

<span class="mw-page-title-main">Pennsylvania Railroad class R1</span> American electric locomotive prototype

The Pennsylvania Railroad's class R1 comprised a single prototype electric locomotive constructed in 1934 by the Baldwin Locomotive Works of Philadelphia, Pennsylvania, US, with the electrical equipment by Westinghouse.

The Pennsylvania Railroad class Q1, #6130, was a single experimental steam locomotive designed for dual service. The locomotive entered service in 1942, and retired in 1949 after accumulating a relatively low 165,000 service miles.

<span class="mw-page-title-main">Pennsylvania Railroad Q2 class</span>

The Pennsylvania Railroad's class Q2 comprised one prototype and twenty-five production duplex steam locomotives of 4-4-6-4 wheel arrangement built between 1944 and 1945.

The Pennsylvania Railroad Class E6 was the final type of 4-4-2 "Atlantic" locomotive built for the company, and second only to the Milwaukee Road's streamlined class A in size, speed and power. Although quickly replaced on the fastest trains by the larger K4s Pacifics, the E6 remained a popular locomotive on lesser services and some lasted until 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.

<span class="mw-page-title-main">Pennsylvania Railroad L1 class</span> Class of 574 American 2-8-2 locomotives

Pennsylvania Railroad Class L1s were 2-8-2 "Mikado"-type steam locomotives that were used on the Pennsylvania Railroad during the early twentieth century. These 574 locomotives were manufactured between 1914 and 1919 by the railroad's own Juniata Shops as well as the Baldwin Locomotive Works (205) and the Lima Locomotive Works (25).

<span class="mw-page-title-main">Pennsylvania Railroad 1361</span> Preserved PRR K4 class 4-6-2 locomotive

Pennsylvania Railroad 1361 is a 4-6-2 K4 "Pacific" type steam locomotive built in May 1918 by the Pennsylvania Railroad's (PRR) Juniata Shops in Altoona, Pennsylvania. It hauled mainline passenger trains in Pennsylvania and commuter trains in Central New Jersey on the PRR until its retirement from revenue service in 1956. Restored to operating condition for excursion service in 1987, No. 1361 and its only surviving sister locomotive, No. 3750, were designated as the official state steam locomotives by the Pennsylvania General Assembly. In late 1988, it was sidelined due to mechanical problems and was currently owned by the Railroaders Memorial Museum (RMM) in Altoona, Pennsylvania, who were currently getting No. 1361 back to operation.

Pennsylvania Railroad 1737 was a 4-6-2 Pacific type K4 class steam locomotive built in 1914 as the first of its class and would haul heavier passenger trains that the smaller E class 4-4-2 Atlantics could not handle such as the PRR's flagship passenger train, the Broadway Limited. In the 1930s, as the PRR had increased passenger service time tables, the trains became longer and heavier than a single K4s could handle, necessitating double-heading with a second engine. The "Standard Railroad Of The World" made attempts to replace the 1737 and its classmates with larger, more powerful classes including: K5, S1, and the T1, none of which were successful; thus, the K4s continued hauling passenger trains until the Pennsylvania Railroad replaced steam locomotives with the increasingly-popular and less-costly diesel-electric locomotives in 1957.

<span class="mw-page-title-main">Pennsylvania Railroad class G5</span> United States historic place

The Pennsylvania Railroad G5 is a class of 4-6-0 steam locomotives built by the PRR's Juniata Shops in the mid-late 1920s. It was designed for passenger trains, particularly on commuter lines, and became a fixture on suburban railroads until the mid-1950s.

<span class="mw-page-title-main">Pennsylvania Railroad class E2</span>

The Pennsylvania Railroad's class E2, E3, E7 steam locomotives were of the 4-4-2 "Atlantic" passenger type, frequently called light Atlantics after the introduction of the heavier E6 Atlantics. All were similar in size and boiler capacity but differed in firebox type, valves and valve gear and cylinder diameter. Classes E2 and E3 were built simultaneously.

<span class="mw-page-title-main">Duplex locomotive</span> Type of steam locomotive

A duplex locomotive is a steam locomotive that divides the driving force on its wheels by using two pairs of cylinders rigidly mounted to a single locomotive frame; it is not an articulated locomotive. The concept was first used in France in 1863, but was particularly developed in the early 1930s by the Baldwin Locomotive Works, the largest commercial builder of steam locomotives in North America, under the supervision of its then chief engineer, Ralph P. Johnson.

<span class="mw-page-title-main">Pennsylvania Railroad 5550</span> PRR T-1 class 4-4-4-4 locomotive under construction

Pennsylvania Railroad 5550 is a mainline duplex drive steam locomotive under construction in the United States. With an estimated completion by 2030, the locomotive will become the 53rd example of the Pennsylvania Railroad's T1 steam locomotive class and the only operational locomotive of its type, as well as the largest steam locomotive built in the United States since 1952. The estimated cost of PRR 5550 was originally $10 million, but an updated projected cost of $7 million was released with the acquisition of an existing long-haul tender from the Western New York Railway Historical Society in August 2017. Construction began in 2014 with the casting of the locomotive's keystone-shaped number plate. As of February 2024 the locomotive was 43% complete.

The Pennsylvania Railroad's class K29s comprised a single experimental 4-6-2 "Pacific" type steam locomotive. Constructed by Alco-Schenectady, it was given road number 3395. Although only one demonstrator was constructed, the K29s would become the basis for the highly successful K4s Pacifics and L1s Mikados. The lone example spent most of its life on the PRR's Pittsburgh division main line and was retired around 1929.

References

  1. 1 2 Staufer 1962, p. 217.
  2. ↑ Staufer 1962, p. 225.
  3. 1 2 3 4 5 6 "FAQ Section - The T1 Trust". The Pennsylvania Railroad T1 Steam Locomotive Trust. 2016. Archived from the original on 24 August 2019. Retrieved 23 April 2017.
  4. ↑ Reed 1972, p. 271.
  5. ↑ Reed 1972, p. 275.
  6. 1 2 Llanso, Steve; Duley, Richard. "Pennsylvania 4-4-4-4, 6-4-4-6, etc. "Duplex Drive" Locomotives of the USA". SteamLocomotive.com. Archived from the original on 27 April 2017. Retrieved 23 April 2017.
  7. ↑ "In Defense of the 5500s", Volume 41, Number 1, Pennsylvania Railroad Technical and Historical Society Magazine, Spring, 2008
  8. ↑ Kerr, Douglas A. (October 16, 2011). "Spring Equalization for Steam Locomotives" (PDF). Retrieved August 24, 2019.
  9. ↑ "Pennsy T1 comeback? Ten questions and answers for the T1 Trust", Volume 75, Number 5, Trains Magazine, May 2015.
  10. ↑ Baer, Christopher T. "Chronology of the Pennsylvania Railroad Company its Predecessors and Successors - 1940" (PDF). Retrieved 24 August 2019.
  11. ↑ "Streamlimed Locomotives of the Swing Era" . Retrieved August 20, 2016.
  12. ↑ Rivanna Chapter, National Railway Historical Society (2005). "This Month in Railroad History: August" . Retrieved 2006-08-25.
  13. ↑ Reed 1972, p. 279.
  14. ↑ "Pennsylvania Railroad 4-4-4-4 T1 Locomotive". 20 June 2020.
  15. ↑ Withuhn, William L. (1 March 2019). American Steam Locomotives: Design and Development, 1880–1960. Indiana University Press. pp. 361–386. ISBN   978-0253039330.
  16. ↑ Johnson, Jason; Noble, Bradford (December 2015). "Building from the Rails, Up: The PRR T1 Trust" (PDF). Railfan and Railroad. Swedesboro, NJ: Whiteriver Productions. Archived from the original (PDF) on March 17, 2016. Retrieved August 24, 2019.
  17. ↑ "Latest News (March 24, 2019)". The T1 Trust. Archived from the original on August 24, 2019. Retrieved August 24, 2019.
  18. ↑ Lemony Snicket's A Series of Unfortunate Events - Train Scene

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