Well the official definition of a crank goes something like this;
"Crank" is a pejorative term for a person who
holds some belief which the vast majority of his contemporaries would consider counterfactual, clings to this belief in the face of all counterarguments or evidence presented to him.
The term implies that
a "cranky" belief is so wildly at variance with some commonly accepted truth as to be ludicrous, arguing with the crank is useless, because he will invariably dismiss all evidence or arguments which contradict his cranky belief.
Common synonyms for "crank" include kook and crackpot.
The word quack is usually reserved for someone who promotes a medical remedy or practice which he knows to be ineffective.
In the fire service I think you can safely say that a crank is someone that lives breathes and eats fire. Someone that is extremely passionate about the service and will generally put up strong arguments for change. Don't try to argue with a crank because they will always completely baffle you with technical specifications and useless information that will make you believe they really know what they are talking about.
I would say that many of the busier brigades would have a reasonable level of crankness, however the further afield you travel the less cranky they seem.
..... CRANKS OF THE WORLD UNITE .....