This 1955 Tucker Sno-Cat Type 743 Double Drive is in a bad way, half way across that crevass, and you'd think there is no way to save it from falling in, if any attempt at pulling it out were undertaken. This video shows how it was done... maybe not for this sno-cat, but one in a similar predicament.
Video via: http://stipistop.com/
For photos I took of one up close: http://choosingscars.blogspot.com/2009/07/tucker-snow-cat-pioneering-vehicle-of.html
