Double heading

In railroad terminology, double heading indicates the use of two locomotives at the front of a train,[1] each operated individually by its own crew.

In Britain, the Midland Railway used to use double-heading often, because it built only small, light locomotives, which were often not powerful enough to haul the trains alone.

Several accidents on the Midland system were indirectly caused by this 'small engine policy' and the resulting reliance on double-heading.

This should not be confused with the totally different procedure of adding a banking engine to the rear of a train to assist up a hill or away from a heavy start.

Despite requiring time-consuming shunting operations each time an engine had to be added to or removed from a train under these rules, they remained in place on parts of the GWR until nationalisation in 1948.