D&H 599 is the prototype for a batch of high horsepower locomotives that were built for the electrification of the D&H line from Schenectady to Montréal. It is based on the EMD/ASEA GM10B and GF6C motors (except taking DC power from the overhead wire) and was (almost) a perfect success.

The problem that the PV&T was trying to solve was that high powered DC drive locomotives tended to be really slippery, so being able to get >8kHp out of an 8 axle machine was an iffy proposition. The GM10B’s being able to get 10kHP to the rails on a six axle machine, now that was something that was worth looking at.

What EMD proposed, after consultation with the Portland Shops engineering department, was an extension of the traditional class B-style two-section unit – two (stretched) sections on 5 articulated trucks, with the center truck supporting an articulation joint between the sections.

The motor was built at the GMD facility in London (Ontario), then shipped to Portland for acceptance testing. The testing was a complete success, but the electrical department didn’t particularly like the angular design of the prototype, so followup orders had their carbody shells built in Portland and shipped to the EMD plant in Illinois for completion.

The class I’s are ~220 tons (the Portland-built I2s are slightly lighter), putting out 10000HP, and capable of pulling long freights at line speed over the more mountainous parts of the railroad.

This motor operated until 2024, when it was retired to the museum fleet in Saint-Constant (Québec).