Who assigns military callsigns?

I live near an airport that was an Air Force field and, although now commercial, still has some military activity. Frequently there are KC-135s flying around the area with callsigns such “EDDIE67”. Who assigns those? Is this what the military use to refer to their flights or is that a call to amuse the public? The names they come up with are kind of funny.

https://henney.com/chm/callsign.htm

These what you see are assigned randomly

I am living close to Ramstein Air Base and beside the “official callsigns” i see pretty often fantasy names like “VALOR” “ATTACK” “NACHO” “REDEYE” followed by a single number.

Currently you can find two F16 with interesting names over Romania:

Depends on a lot of factors. I dont know if it is still available today but when I was an Navy Aircrewman the Nav would pick Callsigns on transit flights. Lots of flights used the squadron Calligns. Like when I flew for VQ-1 our tail flash was PR so we were known as Peter Rabbit. In VQ-2 we were known as Sandman, so Sandman XX. VQ-2 had a second one of RANGER so we would be Ranger XX (usually the nose number). Sometimes the Nav would ask one of us what sounded good. My Favorite was when we flew into Miami Center with our picked callsign of BR549 … Caused some concern with them.

Mission callsigns were assigned by the Command that we were working for.

HEE-HAW! (20 characters)

Wait! That’s part of my email address and user name on many websites. I rarely fly into MIA but regularly into TMB.

My nearest airport houses an F-15 training facility. While I don’t see those fighters in ADS-B their F-5 targets show up as VILLN(numeral).

“Viper” is a common US Air Force nickname for the F-16, so it’s unsurprising that they would choose that as an identifier.

C-17s doing landing practice at Wright Patt AFB often use RHINO.

There’s one pilot with a good radio voice who calls in as RHINO NINE OH

i recently spotted a E-4B Floating the Callsign “Order 66” which IMMEDIATELY threw me to Star Wars Episode 3 “Revenge of the Sith” with the Emperor giving the Clone wide Order “Execute Order 66”