The Combat Arms Training and Maintence (CATM) section of an Air Force Security Forces Squadron are firearms instructors and maintainers. The tendency for some people to call CATM "combat arms" confuses people who do not know much about what they do. So, in a nutshell they are a group of Air Force cops who went to an extra school to learn how to be firearms instructors and how to repair and maintain weapons.
John77 - Being a Security Policeman in the Air National Guard is a good gig but, I need to warn you that while law enforcement is a big part of the Security Forces career field but, the Air National Guard Bases here in Massachusetts do not have much of a law enforcement mission so they concentrate mostly on base security. Example: On a military base most of your police work comes from situations in base housing, the club on base, shopliftings at the exchange, etc. At Otis the housing area, club, and exchange are managed by the Coast Guard which employs a rent-a-cop security company to "Police" their areas. This translates into a lack of law enforcement activity for the Otis SP's. It is even worse at Barnes ANGB in Westfield. They are a tenent at a small municipal airport, not much police work to be done there. Westover ARB does have a law enforcement misson, but by far the best law enforcement mission for Air Force SP's in Massachusetts is at Hanscom Air Force Base. Hanscom is an active duty base and about 30,000 people work at Hanscom, mostly civilians. Additionally, Hanscom has a housing area, exchange, club, etc. Hanscom is not the crime capitol of the Air Force by any means, but you will do more police work at Hanscom then at any other Air Force installation in Massachusetts. If you are interested in Hanscom you will need to see an Air Force Reserve recuiter. There is one in Braintree in the basement level of the south shore plaza. Tell hime you are interested in the IMA program and that you want to be a cop at Hanscom. He might try to talk you into Westover ARB but it's your choice. Also, the IMA program is a bit more selective so unless you are prior service military you may not be selected, in that case one of the other bases may be your only option and then you can transfer after a few years. Maybe sooner if Otis does end being selected for closure.
Deployments - Most deployments for AF reserve and Air National Guard cops are currently being filled by volunteers. Also the standard AF deployment is anywhere from 3-6 months. Not bad compared to the Army's one year or more deployments.