The Great Northern Railway's class W-1 comprised two electric locomotive

Electric locomotive

An electric locomotive is a locomotive powered by electricity from overhead lines, a third rail or an on-board energy storage device...

s with AAR B-D+D-B wheel arrangements. The locomotives were used on the 73 miles (117.5 km) electrified portion of the railroad, from Wenatchee, Washington

Wenatchee, Washington

Wenatchee is located in North Central Washington and is the largest city and county seat of Chelan County, Washington, United States. The population within the city limits in 2010 was 31,925...

 to Skykomish, Washington

Skykomish, Washington

As of the census of 2000, there were 214 people, 104 households, and 58 families residing in the town. The population density was 623.2 people per square mile . There were 162 housing units at an average density of 471.8 per square mile...

, including the Cascade Tunnel

Cascade Tunnel

The Cascade Tunnel refers to two tunnels at Stevens Pass through the Cascade Mountains, approximately to the east of Everett, Washington. The first Cascade Tunnel was a 2.63-mile long single track railroad, built by the Great Northern Railway in 1900 to avoid problems caused by heavy winter...

.

The 5000 hp W-1 motor-generator

Motor-generator

A motor-generator is a device for converting electrical power to another form. Motor-generator sets are used to convert frequency, voltage, or phase of power. They may also be used to isolate electrical loads from the electrical power supply line...

 locomotives were built at General Electric

General Electric

General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

's Erie works in 1947. Numbered 5018 and 5019, they were the largest single-unit electric locomotives used in North America.

The 5018 and 5019 were retired in 1956, with the 5019 scrapped in 1959. The 5018 was sold to the Union Pacific

Union Pacific Railroad

The Union Pacific Railroad , headquartered in Omaha, Nebraska, is the largest railroad network in the United States. James R. Young is president, CEO and Chairman....

, who used its body and running gear as part of an unsuccessful experimental coal burning gas turbine-electric locomotive

Gas turbine-electric locomotive

A gas turbine - electric locomotive, or GTEL, is a locomotive that uses a gas turbine to drive an electric generator or alternator. The electric current thus produced is used to power traction motors. This type of locomotive was first experimented with during the Second World War, but reached its...

 #80.