The tests were undertaken to establish the following:
 | The price in terms of coal and water of hauling different train loads and different speeds over given routes |
| An indication of the level of efficiency of the locomotive |
| Means of comparing one locomotive with another on a common basis |
Testing was undertaken on the static test plant at Rugby and on the line between Settle and Carlisle the actual tests being monitored between Lazonby and Crosby Garrett, a distance of approx 25 miles. The amount of coal and water used was carefully monitored, the tender being divided in two such that weighed bags of coal for the test were carried on one side and ordinary loose coal for transit and shunting moves on the other.
Here are a few pictures of the tests and a summary graph.
