USAAF Specialists arm badges
 

Hi gentlemen,

I am looking for information who from USAAF personnel used the blue triangle "specialists" arm patches... like the "engineering", "weather", "communications"

My question is if these patches were used by just ground crews or also by flying crews and when...
So if for examplr an Top-turret gunner / engineer on a B-17 can use the "engineering" patch on his uniform or Ike jacket..

Some examples what I mean can be found on e-bay under numbers:
290156097935
290155174750
200146361548
290154534454

Any info will be greatly appreciated.
Thanks, Jan