Locomotive

A self-propelled unit of equipment which can be used in train service. (49CFR236)

A piece of ontrack equipment other than hi-rail, specialized maintenance, or other similar equipment; 1) With one or more propelling motors designed for moving other equipment; 2) With one or more propelling motors designed to carry freight or passenger traffic or both; or 3) Without propelling motors but with one or more control stands. (49CFR229) (UN1)

A self-propelled unit of equipment designed primarily for moving other equipment. It does not include self-propelled passenger cars. (49CFR223)

A self-propelled unit of equipment designed for moving other railroad rolling equipment in revenue service including a self-propelled unit designed to carry freight or passenger traffic, or both, and may consist of one or more units operated from a single control. (49CFR218) (49CFR221) (FRA3) (FRA4)

See also Rail, Railroad, Railway, Train.

Locomotives are units propelled by any form of energy, or a combination of such units operated from a single control station, used in train or yard service