Another view of GMC's LWT12 -- the "Aerotrain" -- which was designed to be cheap, fast transportation. Only three were built in McCook, Illinois in 1955. Prototypes were tested by the Pennsy and UP, among others, which quickly revealed the LWT12 to be severly underpowered and providing a very rough ride -- the passenger cars were low, built by modifying GMC bus bodies. All three ended their run on commuter service on the Rock Island. Two still exist today -- one at the National Railroad Museum in Green Bay and the other at the National Museum of Transportation in St. Louis.