One of the views we don't often get in photos is of the top of the tank. Fiding the enclosed that has a good view of the top of a Mk IV I notice that the number 24 is painted in large digits on the top of the cab. The only point that I can think of is for the benefit of RFC contact patrols so they can report the tanks position back to HQ. Does anyone know if this was a common/standard or rare marking?
I could see this being useful for avoiding friendly fire. With the Germans using captured tanks, I could see the possibility of artillery spotter planes bringing down a wall of shells on you be accident. Just a thought.
There is a page http://www.landships.freeservers.com/BritSerials.htm that describes the markings. I've seen a few photos including Beute tanks that have the call sign on top of the cab. The difficulty is in finding photos of the cab roof.
P.S.: Obviously, the Beute tank didn't have the call sign but an Eisenkreuz. My mistake.