Question/idea : hand signal

Hello

I read in some books that lot of "old russian" planes were not equiped of radio in 1941. And sometimes only flight leader had one during a mission. So the order were given with hand signal.

With the open cockpit i'm interrested to know if it's something that we can hope for in the future or not ? Something that look like jester menu but for moving the pilot arms ? :pilotfly:

Thanks :)