I recently subscribed to Trains Unlimited, which provides digital access to every issue of Model Railroader, Trains, Classic Trains and other Kalmbach train magazines (including new ones as they are released). And I found something interesting in the March, 2002 issue:
They have a map of traffic density on the New Haven in 1955. There are two similar maps in the Characteristic Charts (once published by NHRHTA), but they are for 1918 and 1919. I won't reproduce the Trains map here, but let's look at the data for New Britain.
The maps in the Characteristic Charts indicate the number of trains and average daily tonnage:
- 6 westbound, 3624 tons
- 6 eastbound, 5592 tons
What's interesting, though, is they indicate the traffic in each segment. In this case, between Plainville and New Britain, and vice versa. By looking at the next segments, we can deduce the traffic in New Britain:
New Britain to Hartford is:
- 6 westbound, 3221 tons
- 6 eastbound, 4846 tons
So on the westbound run, an average of 403 tons was added in New Britain, and on eastbound trains 746 tons were dropped in New Britain.
The Berlin Line doesn't have any traffic noted, but there's an arrow that indicates "Switching Service."
I can't do a similar calculation west of Plainville because there are 7 trains each way.
- 8 westbound, 5826 tons, 1657 tons picked up in New Britain
- 8 eastbound, but I can't read the tonnage.
Number of Cars
I don't know what the average load was for each freight car, but I do know that the average load was less than the capacity of the cars based on other research. So here are two estimates using the 1918 data:
- 30 ton cars, 13 cars westbound, 25 cars eastbound.
- 20 ton cars, 20 cars westbound, 37 cars eastbound.
So how does this compare to 1955?
The cool thing about the map in Trains magazine is that it gives the number of cars instead of tonnage.
- New Britain to Plainville: 3 trains, 101 cars, both ways
- New Britain to Berlin: 3 trains, 113 cars
- Berlin to New Britain: 3 trains, 121 cars
Since all trains route over the Berlin Line, that gives us 12 cars dropped and 20 cars picked up.
One thing to keep in mind is that this shows us the net change but hides equal numbers of drops/picks. In other words, it could be 32 cars dropped and 40 cars picked, with a net 12 and 20. Those three trains in 1955 served the Canal Line north of Plainville or the New Hartford Branch.
- New Hartford Branch is 1 train, 8 cars both ways
- Plainville to Westfield is 2 trains, 88/86 cars
- Williamsburg/Northampton is 1 train, 14/15 cars
- Holyoke is 1 train, 51/34 cars
The imbalance in Holyoke is probably outbound cars being interchanged.
So it won't actually give us a specific count of cars to/from New Britain, but it does give us some more information to help make sure that the amount of traffic looks right. As modelers I think we sometimes have the tendency to run more cars during an ops session than is prototypical. That's fine, of course, and it's often because we want to have enough to do during a given session. In the near future I'll explore an alternative to adding additional traffic to provide enough work for your operators.