09-14-2009, 07:26 PM
It's not fuel, that is water coming out of the water tank. That unit is used in passenger service with a steam generator. It would appear that they used shorter air tanks so that they could leave the dynamic brakes clear. In the case of the Santa Fe, they had a few freight Gp7's and 9's equipped with steam generators. They also had a few blue and yellow f-units equipped with steam generators in the b units that could be used in either freight or passenger service. I think that way they could cover whatever motive power requirements they faced whether for extra freight power or in case needed for passenger power for extra sections of passenger trains. I don't think the geeps or the blue and yellow f's were used on name trains like the Chief or Super Chief, although they might have been used on the Grand Canyon. They were used quite often in So Cal on the Del Mar specials, and I think I've seen pictures of them pulling the San Diegan on occasion.