That's an interesting point, I tried to search but I couldn't find any examples. Can you really run a watercooled engine without coolant or a radiator in arctic (-40 to -50C ambient temperatures?). Its not like an air cooled engine designed for natural convection.
Seems like at the very least they could run the engine as long as possible until its about to overheat, then turn it off and it will very quickly return to operable temperatures in the very cold conditions. Certainly better than dying outside in Siberia!
One possible hitch: if you lose ALL your coolant, you might have a hard time monitoring your engine temperature, as the usual temp gauge monitors coolant temp.
Might still be fine, but... By the time you know it ain't, could easily be too late.
Seems like at the very least they could run the engine as long as possible until its about to overheat, then turn it off and it will very quickly return to operable temperatures in the very cold conditions. Certainly better than dying outside in Siberia!