“Now let’s have some fun”

After completing an inspection of my train for hand brakes, retainers and closed angle cocks, I stood at the last car in amazement about the size of the train. This was the longest and heaviest train that I had anything to do with. All night in the cab, the engineer and I talked about making it up the hill. We were not sure if we could make it over the hill but wanted to find out at least how far we would make it.

I walked into the cab and informed the engineer to back up when ready as I started to peel off my wet Carhart rain pants and coat.

“You have a lot of faith that I can get this train moving and up over the hill.”

I knew that we had only 40% of making it up the hill. This would be a battle of traction effort and adhesion versus wet rail and the grade. Our duo locomotives for the evening, a GP15-1 leading the second unit, a GP35 would combine for 98,000 pounds of traction effort, 28 EMD cylinders, and 4,000 horse power. The battle against the grade started.

We started the train in run 2 to get us moving quickly. One of the tracks leaving the scrap yard had a slight down-hill grade that gave us some help, but not that much. We crossed the first crossing with no problem and slipped some on the second crossing. We were moving, but it was not the horse power that kept us moving, it was all traction effort. There was no need yet to run the engine at full throttle since this would only cause the traction motors to slip and spin on the wet rail. The train had movement of about 7-8 mph and the only goal was to keep moving. All 31 cars were on the straight grade, engines in run 5 and would soon face an uphill curve in the track. This is where the horse power would come in to provide the power needed to maintain traction effort that would result in us still moving. We enter the curve and started to slip. These two locomotives were couple short hood to short hood which allowed me to see the wheel slip light reflection flashing from the trailing locomotive in my window. Rapidly, we started to loss speed once more cars enter the curve. In a finally assault at about 2 MPH, the engineer notched up the locos only to have them pull some and slip. This lasted only about 1 car length before we stalled in notch 8. We ended up cutting 6 cars off the head end and placing them on a siding that was less than a quarter mile away. While walking back to make the cut, I noticed that the air was filled with a very fine sand dust. This was the result of the sanders sanding the railing, then being crushed by the locomotive wheel and the traction motor blowers blowing it into the air. Pulling the remaining 25 cars was no problem. We soon tied the 25 to the 6 at the side track and headed home.

This night we failed because of adhesion, not horse power. You need power at speed to keep a train moving at track speed. In slow, hard pulls, it comes down to traction effort and adhesion.

In an upcoming post, I will compare turbo charged and roots blown locomotives.