Pennsylvania Railroad class K29s

The Pennsylvania Railroad's class K29s comprised 1 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.[4]

K29s class
Type and origin Power type Steam Builder Alco-Schenectady Build date 1911 Total produced 1
Specifications Configuration: ​  • Whyte 4-6-2 Gauge 4 ft 8 ^1⁄2 in (1,435 mm)[1] Driver dia. 80 in (2,000 mm)[2] Wheelbase:  • Engine 36 ft 5 in (11,100 mm)[1] Loco weight 317,550 lb (144,038 kg)[3] Tender weight 175,700 lb (79,696 kg)[1] Total weight 492,700 lb (223,485 kg) Tender type Class 80-P-83[4] Fuel type coal[1] Fuel capacity 14 tons[4] Water cap 8,280 imp gal (37,600 l; 9,940 US gal) Firebox type Radial stay  • Firegrate area 54 sq ft (5.0 m^2) Heating surface 4,625 sq ft (430 m^2)[1]  • Firebox 253 sq ft (23.5 m^2) Valve gear Walschaerts[2]
Performance figures Tractive effort 43,375 lbf (193 kN)[3]
Career Operators Pennsylvania Railroad Class K29s Number in class 1 Numbers 3395 Locale PRR Pittsburgh Division, Pennsylvania, United States Retired 1929 Disposition Scrapped in 1929

History

The sole K29s, PRR 3395, was constructed by the American Locomotive Company's Schenectady works in 1911 as a demonstrator engine for the Pennsylvania Railroad. The success of the single experimental K29s lead to the development of the equally successful K4s class Pacific and L1s class Mikado locomotives.[4] Despite its success, the K29s was one of only a handful of locomotives constructed by Alco Schenectady as the PRR preferred its own Altoona Works as well the Baldwin Locomotive Works in Philadelphia for large scale locomotive production.[3] The sole K29s spent its entire operating life on the PRR's Pittsburg Division main line pulling limited passenger trains and being used as a helper engine. Rumors circulated stating the K29s was able to haul 13 full sized passenger cars unassisted on an uphill grade between Gallitzin, Pennsylvania and Altoona, Pennsylvania. By 1929 however, the K29s was stricken from the PRR's locomotive roster.[4]

Specifications

The K29s had six driving wheels measuring 80 inches (203 cm) in diameter each and a 36 feet 5 inches (11.10 m) total wheelbase. The total weight including engine and tender was 492,700 pounds (223,500 kg), while the engine alone weighed 317,550 pounds (144,040 kg).[1] The K29s used the Walschaerts valve gear, with 27 in × 28 in (686 mm × 711 mm) cylinders.[1][2] The tractive effort was 43,375 pounds-force (193 kN).[3] It also had a total firebox heating surface of 4,625 square feet (429.7 m²) and a fire grate of 66.1 square feet (6.14 m²).[1] It was paired with a Class 80-P-83 tender that could carry 8,280 US gallons (31,300 l; 6,890 imp gal) of water and 14 tons of soft coal.[4][1] The K29s had an unusually massive boiler for its time, measuring between 81.25 inches (2,064 mm) and 89 inches (2,300 mm) in diameter and 22 feet (6.7 m) in length from firebox to smokebox door.[4][1] Most of the basic specifications can also be found on the succeeding K4s Pacifics, which was directly developed from the K29s.[5]

References

1. Wright, Roydon Vincent; Swift, Porter La Forrest (1912). Locomotive Dictionary: Definitions and Illustrations of American Locomotives, Their Parts and Equipment, Together with Typical Illustrations of Machine Tools and Devices Used in Their Maintenance and Repair. Simmons-Boardman Publishing Company.
2. Test Department, Pennsylvania Railroad (1915). Locomotive Testing Plant at Altoona, Pa: Bulletins. Altoona, Pennsylvania. p. 5.
3. Staufer & Pennypacker 1962, p. 146.
4. Staufer & Pennypacker 1962, p. 144.
5. Staufer & Pennypacker 1962, p. 159.

Further reading

• Staufer, Alvin F.; Pennypacker, Bert (1962). Pennsy Power: Steam and Electric Locomotives of the Pennsylvania Railroad, 1900-1957. Research by Martin Flattley. Carollton, Ohio: Alvin F. Staufer. ISBN 978-0-9445-1304-0.