The only reason I fished this one out is how many viewers have ever seen the top of a UP "Big Blow" Turbine where all that noise came from. (They were eventually outlawed from running in Sou. Calif.) It is that large hole, a short stack, on the rear end of this center unit --- the turbine. It leans backwards just a bit, and notice how blackened the top of the fuel tender is. This No. 21 was turning on a wye within he vast North Platte, Nebr. yard when I snapped it March 21, 1969