1945 Pennsylvania Railroad
NO. 5505 4-4-4-4
Two LOCOMOTIVES of this type were built by Baldwin's in 1942 and operated experimentally in main-line service as well as upon the Altoona Test Plant. The 5505 was one of another, fifty, the biggest fleet of four cylinder rigid-frame locomotives, built as the result of the satisfactory performance of the first two. They are direct descendants of the S1 in general characteristics except that instead of having six-wheel leading and trailing trucks, these are four-wheel, and a different streamlining treatment has been applied. The tenders are the second largest ever built and permit runs of 713 miles from Harrisburg to Chicago with only one coaling stop at Millbrook, Ohio. Poppet valves, roller bearings throughout, including rods and crossheads and forced feed oil lubrication at eighty eight points, were factors contributing to 93 to 94 per cent machine efficiency registered on tests. The T1's were designed to handle 880-ton trains at 100 miles an hour on level track and have been used in heaviest passenger service until superseded by diesels.

BuIlder-Baldwin Locomotive
Works (27)
Altoona Shops (25)
Fuel-41 tons
Cylinders (4)-18¾" X 26"
Weight, total-953,370 lb.
Steam Pressure-300 lb.
Length, coupler to coupler-122 feet 9¾ inches
Water- 19,500 gal.
Dia. Drivers-80"
Tractive Effort-64,650 lb.
R.R. Class-T1