BTW, it is noteworthy that the War Production Board did not say that the
D&RGW design was not worthy but, rather, simply said that they should use
the UP designed engines which were actually built for UP. They apparently
concluded that D&RGW had a larger need for them than UP. I am curious,
incidentally, about the D&RGW engines and their capabilities. Similarly
larger NP Challengers did not produce the performance expected because the
front end nozzles were relatively smaller in order to keep a strong draft
from blowing the dirt-like Redbud NP coal off the grates and up the stack.
The result was relatively high back pressures. The sorce of fuel did matter.

Mike Brock