Broadway Limited Imports N PRR T1 Duplex #5545 Silver w/Red Fantasy Prgn4 BLI8028 N Locomotives

Introduction

The T1's were duplex locomotives - this means they had two sets of drivers, each with its own pair of cylinders and rods. However, the T1s were not articulated locomotives, but used one rigid frame. With this design, the cylinders could be smaller and the weight of side rods and main rods could be reduced. This duplex design with lighter machinery, shorter cylinder stroke, less wear and tear due to small moving parts and the use of poppet valves allowed the T1's to travel at extremely fast speeds. Unfortunately they were also prone to wheelslip and maintenance issues that the Pennsy struggled to work through - especially the fact that the poppet valves could not withstand sustained operation at 100 mph speeds. These problems likely could have been resolved with some modest design changes, but the PRR, and steam in general, ran out of time. In 1948, the PRR dieselized all of its first-class prime trains and the T1s were downgraded to haul secondary trains. Some were withdrawn from service in 1949, and all were retired by 1952