Air conditioned hangar - not quite. The hangar is at the current ambient, which is 102F (but it is a dry heat).
I'm not sure if the number of blades would make much difference, but I do remember my Canadian Air Force friends who were flying OH-58A models in Germany telling me that they could always win a dog fight with the French Gazelles across the river by rolling rapidly to the direction that would torque spike the Gazelle (and give a torque decrease on the OH-58). Not that dog fights between helicopters ever happened of course...