Communication Breakdown - S10-E6
Visible crew/equipment: While Colonel Potter and Margaret are with Charles, a nurse sees them and announces the presence of a newspaper, then when everyone gathers around Charles while he sets the reading rules, there's a man with blondish shoulder length hair and a beard, wearing a blue button down shirt and white pants who's standing in the background, partially hidden by the signpost.
Answer: Even an Army field hospital would have SOME weapons for self-defense if the enemy attacked. What's meant is that it's not a combat outfit, and therefore wouldn't have enough weapons to actually attack anyone. (It's also mentioned a few times that the Officer of the Watch is supposed to carry a pistol at all times, but Hawkeye refuses to do it when he's in charge and Colonels Blake and Potter don't enforce the rule).
Captain Defenestrator