Prototype
The NW-2 is a switcher engine. EMD built them from 1939 to 1949. The engine is recognizable by its half-height front radiator grill. It has a minimum track radius of 100 feet (19-inch radius in S-scale). It maximum speed was 60 miles per hour. It measured 44'5" long, 14'5" tall, and 10'0" wide. It weighed 248,000lbs.

The Pennsylvania Railroad added these engines to its roster in 1941. It classified the NW-2 engine as an ES10, which stands for EMD Switcher with a 1000hp (12-cylinder) engine. The interesting history of road number 5912 was that it was originally road number 3909 (October, 1941), but was renumbered in 1942.

Prototype drawings of this engine are available on George Elwood's web site. The prototype operating manual is also available on his web site.

I have yet to find a prototype photo of a PRR NW-2, so the one above of the Penn Central's #8648 in 1972 will have to do for now. The photo came from the Penn Central Railroad Online web site. I don't claim the copyright. The web site states that this engine came from the Pennsylvania Railroad and not the New York Central.

This photo is of CR9255 which is an ex-PRR NW-2 that had "PC" applied but was never re-painted. The photo came from the Conrail Cyclopedia web site. I don't claim the copyright. This site lists all the Conrail NW-2s.

Model
I have ordered the S Scale Helper Service's PRR NW-2 #5912 with the new Tsunami Diesel sound decoder. The PRR Chartiers Branch used diesel switcher engines to service the industries along the line, so this is a perfect match.

Since this engine was built after 1932, it used the Type E couplers, which have an 11-inch knuckle. The S Helper Service #01295 coupler seems to be a very close fit, so that will be the one to be installed. If Sergent Engineering ever makes S-scale couplers again, I will upgrade to those. They appear to be much more realistic, but the company seems to have stopped making them.