The Pennsylvania Railroad's K4s 4-6-2 "Pacific" (425 built 1914–1928, PRR Altoona, Baldwin) was their premier passenger-hauling steam locomotive from 1914 through the end of steam on the PRR in 1957.
Attempts were made to replace the K4s, including the K5 and the T1 duplex locomotive, but none was really successful, and the K4s hauled the vast majority of express passenger trains until replaced by diesel locomotives. The K4s was not powerful enough for the heavier trains it often pulled from the mid-1930s onward, so they were often double or even triple headed. This was effective, but expensive—several crews were needed. The PRR did have the extra locomotives, many having been displaced by electrification.
It is recognized as the State Steam Locomotive of Pennsylvania. On December 18, 1987, Pennsylvania Governor Robert P. Casey signed into law House Bill No. 1211 naming the PRR K4 as the “official” state locomotive, according that title to both K4 survivors, 1361 and 3750.
Pennsylvania Railroad 1223 is a 4-4-0 "American" type steam locomotive built in 1905 for the Pennsylvania Railroad by the railroad's own Altoona Works for passenger service. After being retired from active service, the locomotive ran excursion trains on the Strasburg Railroad in Strasburg, Pennsylvania from 1965 to 1989 when it was removed from service requiring firebox repairs. Currently the engine is on static display at the Railroad Museum of Pennsylvania in Strasburg. It was listed on the National Register of Historic Places in 1979. The 1223 is the only surviving example of the Pennsylvania Railroad D16sb class.
The class D16 locomotives of the Pennsylvania Railroad were the most modern of a long history of 4-4-0 type steam locomotives that the railroad used. The 1223 was home built by the railroad at its Juniata Shops in Altoona, Pennsylvania, in 1905. As built it was a high speed passenger engine with tall driving wheels. However, the 4-4-0 type, long the mainstay of American passenger and freight service, was already becoming outmoded when the 1223 was built, being superseded by ever-larger engines. The Pennsy itself was pioneering steel passenger cars, which the public soon demanded for the implied increases in safety. The 1223 was eventually rebuilt with smaller driving wheels for local freight service, having been replaced on passenger trains by engines like the E6 Atlantics and K4 Pacifics. It was modernized as well, receiving superheaters [the "s" in D-16sb), piston valves, an electric headlight, and other improvements.
The Pennsylvania Railroad's K4s class Pacific number 1737 was the prototype of the class of 4-6-2 steam locomotives that eventually would number 425 locomotives.
The Pennsylvania Railroad in 1914 needed a steam locomotive to haul the passenger trains that the smaller E class Atlantics (4-4-2) could not handle. The 1737 was the first K4s ever built for the PRR. In passenger service, the 1737 would handle passenger trains, like the railroads flagship passenger train, the Broadway Limited. As the 1930s began, the 1737 and the other K4s locomotives would have to double-head passenger trains. This is because the Pennsylvania Railroad had increased passenger service time tables. The K4s Pacifics were unable to keep up with the work. The "Standard Railroad Of The World" made a few attempts to replace the 1737 and its sisters. They were the classes: K5, S1, and the T1. None of the replacements were very successful in railroad service. With these being a failure, the K4s had to continue hauling passenger trains until the Pennsylvania Railroad replaced steam locomotives with the increasingly popular and less costly diesel-electric locomotives in 1957.
The Philippine Nuclear Research Institute is a government body in the Philippines, charged with overseeing the peaceful uses of nuclear technology.
Its main facility was a nuclear research reactor, PRR-1, first commissioned in 1963 as a TRIGA reactor and subsequently modified. As of 2007 it is non-operational since its shut down in 1988.