I have 2. One on each shoulder. Left shoulder is my bomber squadron emblem from the USAF. Right shoulder is my dads attack squadron emblem from the USN. Considering notch marks on my back for each combat sortie I flew on.
I got these right after I left the Air Force at my ex wife's urging. Doubt I would have gotten away with a tattoo while I was still in as it was heavily frowned upon by our CO for officers to have them, especially captain and above.
Ex wife has a tramp stamp. She had it as long as I've known her. She's considering another if we are successful in R.