Captain Kill-a-joke reporting for duty! :)

The place in an airplane where the pilot sits was called a "cockpit" relatively early on, either because it was derived from a term used in sailing, or because it meant "the place where the action is".

You could also interpret it as "the place where the men are", since pilots were often (not always) men, and "cock" means... you know. >_> If you think of it that way, then "cockpit" doesn't really seem correct, if the pilot is a woman. Informally, "box" is a similar term to "cock", except applied to women. "Box office" was an existing term, meaning "the place at the cinema where you can buy a ticket".

So, if the pilot or flight crew are all female, calling the place at the front of the airplane a "box office" instead of a "cockpit" is an old joke.