Rotary Snowblower Main Unit lettered for BNSF. Updated July, 2018, to correct rear trucks turning wrong way.
Thanks to n8phu (Chris) for Beta testing this unit.
INFORMATION: Rotary Snowplows were originally built with steam power, but were rebuilt during the 1950's, with the blade being powered by diesel locomotive traction motors.
They get their electrical power from rebuilt F7B units, that were specifically rebuilt to power the Rotaries, and themselves don't have traction motors. The only electrical power the F7B's provide, goes to powering the traction motors that power the Rotary Snowplow blade or wheel. The F7B units are known as 'snails'.
The Rotaries trucks are rigid to help prevent derailments and keep the Rotary Blade at a constant height from the railhead, also the rotaries are chained to their respective 'snail'. Neither the Rotary nor the snail can move by themselves, and rely totally on attendant locomotives to pull or push them. The Rotary doesn't need the snail and thesedays most are assisted by one or more diesel locomotives which do all the pushing and are controlled by the front Rotary Main Unit cab.