Capt. Harry Wales spent four months in Helmand province in his most recent tour, as a Royal Air Force co-pilot gunner in an Apache attack helicopter crew, CNN reported. He was previously in Afghanistan in 2007 and 2008.
"It used to be very much: front seat, you're firing the whole time," he said. "Now, yes we fire when we have to but essentially we're more of a deterrent than anything else."
Harry acknowledged he had killed insurgents, saying it is sometimes necessary to "take a life to save a life."
"Our job out here is to make sure the guys are safe on the ground and if that means shooting someone who is shooting at them, then we will do it," he said.
Harry is third in line to the British throne, at least until his nephew or niece is born this summer. But he has enjoyed living a "completely normal" life at Camp Bastion, in a barracks fashioned from shipping containers and said he is treated no differently than any other officer.
He told reporters in some ways he would have preferred a smaller base where everyone would be familiar with him. At Camp Bastion, there are always people who have not seen him before.
"For me it's not that normal because I go into the cookhouse and everyone has a good old gawp, and that's one thing that I dislike about being here," he said.
Harry's celebrity status got him into trouble last year when photographs showing him partying naked in Las Vegas hit the Internet. He said he had "let myself and my family down" on that occasion.