The PRR S1 class steam locomotive (nicknamed "The Big Engine") 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. It was the longest and heaviest rigid frame reciprocating steam locomotive that was ever built. The streamlined Art Deco styled shell of the locomotive was designed by Raymond Loewy. The S1 had a unique 6-4-4-6 wheel arrangement, meaning that it had two pairs of cylinders, each driving two pairs of driving wheels. To achieve stability at fast passenger train speeds (above 100 mph), articulation was not used. The S1 was completed on January 31, 1939, at Altoona shop, and was numbered 6100. At 140 ft 2 1/2 in (42.74 m) overall, engine and tender, the S1 was the longest reciprocating steam locomotive ever; it also had the heaviest tender (451,840lb / 205 tonnes), highest tractive effort (76,403 lbf (339.86 kN)) of a passenger steam engine when built and the largest drivers (84 inch diameter) ever used on a locomotive with more than three coupled axles. (info from wikipedia) This locomotive does not have an interior, and isn't compatible with the railway mod, if you would like to add an interior or make it compatible (RailFanEthan?) feel free to. Leave a comment if you would like me to make an unmodded version

Controls: Group 1: HeadLight, Group 2: marker lights, Group 3: Open/Closer roof hatch, Group 4: rear coupler, Group 8: steam, Throttle: Regulator (move) start at a low percentage until you get going, then slowly raise the throttle, VTOL/Trim: Open/Close doors, Yaw: Turn Locomotive, Landing Gear: Independant brake, Roll: Turn Tender, FireGuns: Horn.