The first locomotive built with this arrangement was the Baltimore and Ohio Railroad's sole class N-1 #5600 George H. Emerson, constructed at the B&O's own Mount Clare Shops in May 1937.

To reduce the fixed wheelbase, this locomotive had the two sets of cylinders at opposite ends, so that the rear pair were beside the firebox.

The firebox was an unconventional water tube design which was tested well on other locomotives and needed a large space.

The 4-4-4-4 wheel arrangement proved to be a poor design, as it restricted the firebox size and exposed the cylinders to dust and dirt, causing premature wear.

The T1 class was known for violent uncontrollable wheel slip as well as performance and maintenance issues caused by the Franklin oscillating-cam Poppet valves.

The new build T1 is expected to implement some design improvements to help aid in solving problems encountered by the original 52.