Military Helicopter patrols over NW Arkansas (Fayetteville, AR)

I've lived here in Fayetteville, AR for about a year now and my wife has lived here 20+ years and we've both noticed this to be very unusual and peculiar. I understand there's a base in Fort Smith, which is roughly 3.5 hours away, but these military air patrols are running daily, sometimes 1-3 times a day. I'm not familiar with the types of aircraft, but they all seem to have very long, extended barrels on the front and facing forward.

Anyone else live in NW Arkansas and noticed these? Any ideas why they are flying around and over the Fayetteville area and at such a low altitude? Thanks!