August 19th, 2015, 22:19
Regarding spinners and other fighters, the Fw190A series had a fan behind the spinner and was extremely effective at cooling. The airflow inside the cowling was directed so it actually flowed forward between the BMW's cylinders afaik. Hard to imagine but the designer was one of the best of his era.
Oh Daan, streamlined airflow is not as efficient a coolant as turbulent air, but turbulent causes more drag: the continual engineering problem of trade-off!