Not So Wordless Wednesday on Thursday #18

The PRR T-1...

The Pennsylvania RR by the 1940's had lagged behind most of the other major railroads when it came to passenger steam locomotive development. The K4s 4-6-2 was the front line passenger puller for Pennsy in the 1930's to 1940's but it lacked the pulling power that other railroads had for their premier passenger trains. Passenger trains were getting heavier and heavier and the K4s just didn't have enough power at high speed like the NYC Hudsons (4-6-4) or 4-8-4 Northerns from other railroads did. In the 1930's Pennsy devoted most of its resources to electrification and electric locomotives (i.e... the GG-1) so it fell behind in the steam passenger locomotive race. Anything they did to improve electrification didn't mean a thing west of Harrisburg, PA though, so the New York to Chicago or St. Louis trains of Pennsy were not winning that competitive timetable race. Diesels started appearing in the late 1930's but the Pennsy was slow to get on that train so to speak, and with WWII putting a damper on new diesel locomotive production, the Pennsy was still stuck with its huge fleet of K4s pulling nearly all their passenger trains when the war ended.

Enter the T-1 locomotive. The T-1 was a 4-4-4-4 duplex drive non-articulated steam locomotive built by PRR at Altoona and Baldwin in Philadelphia exclusively for PRR. The one-of-a-kind streamlined design of the locomotive was by Raymond Loewy, who in the industrial engineering world is considered the father of streamlining.

PRR T-1 #5533. Unknown photographer, Creative Commons license.

Two T-1 prototypes were delivered in 1942 and the trials on those two locomotives prompted Pennsy to order 50 more which were delivered in 1945 & 1946. At the time, the T-1 was arguably the most technologically advanced steam locomotive ever built. It was not articulated like other split-driver locomotives and because of this was nicknamed the "rail straightener". The T-1 had more than enough horsepower to pull a 16-car passenger train at 100mph or more on flat terrain. 120mph was easily achievable and there were unofficial reports that some had reached 140mph. The Pennsy never tried to go for a world speed record with the T-1 though, which it probably would have easily set back in the 1940's. 

There was of course a downside to the T-1. First, it was prone to wheel slippage even at high speed on the rear driver axles and it took a highly skilled engineer to run it at high speeds. Most importantly though, it was very complex and expensive to maintain. The driver rods for instance are roller bearing rods instead of friction bearings common on most other steam locomotives. Violent wheel slippage at high speed could be very dangerous and could cause poppet valve failure.

In a sense, the advanced technology of the T-1 actually led to its downfall and caused the Pennsy to push for dieselization across the entire fleet. Pennsy management eventually realized that the T-1's only made it a couple thousand miles before requiring expensive maintenance overhaul, when at the same time the few diesels on the roster were routinely making it 50,000 plus miles before requiring overhaul. As the 1940's ended, Pennsy was ordering dozens of new EMD E7's and E8's to replace all steam locomotives in passenger service. T-1's were taken off passenger service and lived out their final days pulling fast mail & express trains.

In the early 1950's all of the T-1's were taken out of service and by 1956 all 52 of them had been scrapped. The T-1 had a very short but very profound life.

The T-1 Trust

The T-1 Trust is a non-profit group with plans to build a fully functional T-1 (#5550) from the ground up. From their website, their goal is "To provide mainline steam excursion service and to set the World Speed Record for a steam locomotive".

Check out their website to see their progress.