I've been experimenting with stopping distances, before spacing the signals on a layout, by trying single, double, triple and so on heading on a standard train. I expected the stopping distance to be roughly inversely proportional to the square root of the number of engines. But it is not like that.
The rule applies for double-heading. But add more engines and there is little reduction until you have five or six together, depending I think on their length.
However, if you put pairs of engines at intervals (not too close) along the consist they do have the desired stopping power. So four engines in two pairs will stop the train in half the distance for one engine, six in about 40% of the distance and nine in a third of the distance.
I wish I'd done this experiment earlier rather than just add more engines and watch the trains still whizzing past red lights!
The rule applies for double-heading. But add more engines and there is little reduction until you have five or six together, depending I think on their length.
However, if you put pairs of engines at intervals (not too close) along the consist they do have the desired stopping power. So four engines in two pairs will stop the train in half the distance for one engine, six in about 40% of the distance and nine in a third of the distance.
I wish I'd done this experiment earlier rather than just add more engines and watch the trains still whizzing past red lights!