May 14 1942 brigadier general Stuart C. Godfrey outlined his idea for a
completely new type of engineer unit. His proposed unit would be a highly
mobile engineer battalion with equipment small enough to be transported by
the Waco CG-4A "Hadrian" glider or the Douglas C-47 "Skytrain".
Being air-mobile, those units could be flown very near the front or even
behind enemy lines to rehabilitate recently captured airfields or construct
the most basic type of forward airfields.
The engineer board lost no time in attacking the equipment problem. Acquiring
the support equipment (air compressors, rollers, scrapers, graders, etc.)
proved to be no real problem. Tractors, on the other hand, were quite
another matter. "The machine that came closest to meeting the
requirements was a crawler-type trail tractor that had been developed by the
United States Forest Service at Portland, Oregon. Its size was about that of
a Jeep, it weighed only 3,600 pounds and it was equipped with a master
clutch control that eliminated reverse gear and gave the tractor an equal
range of power and speed for moving ether forward or backward."
The process of development for this unique tractor had begun as early as
1924 when USFS field engineer Ted P. Flynn had attached a counterbalanced
bulldozer blade on a small Cletrac tractor crawler to aid in forest service
road construction. It was this "trail tractor" that had already
caught the eye of the army air force.
In order to expedite the production of the tractor, the engineer board arranged
to have Ted Flynn loaned to Clark equipment company and with 15 of Clark
engineers, the design of the Clarkair CA-1 was developed. While Clark had
never built a crawler before, they certainly knew their way around castings,
gears, axels and production schedules. From two machines, sixteen, one
hundred and sixty-two, and then on to an order for one thousand, the company
showed that they could get the job done.
By the summer of 1943 Clark equipment convinced the engineer board that
American machine and metals of East Moline, Illinois should take over
production in stages. By January of 1944, American Machine and Metals had
taken over the Clarkair project until its cancellation in late 1944.
from the Airborne Aviation Engineers
and the Clark Airborne Crawler by Steve Hansen.