Prince Harry said he was "thrilled to be back" in Britain as he returned home on Wednesday after serving a 20-week tour of duty in Afghanistan.

The 28-year-old Apache attack helicopter co-pilot arrived back on home turf after spending two days' mandatory post-deployment "decompression" time at a British base in Cyprus.

Harry, third in line to the throne, said during his tour that he had killed Taliban fighters, who were taken "out of the game" by his unit if they targeted British soldiers.

Saying he was "quite useful" with his thumbs, he light-heartedly compared pressing the trigger to playing video games, provoking an angry reaction from the Taliban.

But after landing at Brize Norton airbase in southern England, he moderated his line when asked specifically if he had killed Islamist insurgents.

"You get asked to do things that you would expect to do wearing this uniform. That's as simple as that," he told reporters.

Captain Wales, as he is known in the Army Air Corps, reflected on returning home in one piece.

"It's been great, it's a hell of an experience," he said.

"Just thrilled to be back. A bit of blue sky in Cyprus, a bit of decompression, some comedy and back to the snow.

"You do get life experiences that you would get nowhere else out there.

"The best thing about it is to be back.

"I enjoy being a soldier, I enjoy the guys that I work with.

"We, together, the guys wearing the uniform, have gone on and done a damn good job.

"It's been a good effort."

The army officer said he was looking forward to seeing Prince William and his pregnant wife Catherine.

"I'm longing to see my brother and sister-in-law," he said.

"I really am longing to catch up with people behind closed doors. You guys aren't invited," he added, in a trademark dig at the media.

Harry said he had not had time to think about dropping from third to fourth in line to the throne once William and Kate's baby is born in July.

The prince is unlikely to get another turn flying in Afghanistan again before all foreign combat troops withdraw by the end of 2014.

He did not know what lay in store for him this year but said he wanted to carry out more royal duties and charitable work.

"The army will have an idea, I presume, and what that is, I will do," he said.

"Given the opportunity, I'd like to take on some more royal stuff.

"Hopefully there'll be a few gaps that open up."

At Britain's sprawling Camp Bastion base in southern Afghanistan, Harry slept in a tent and a shipping container.

In his two-man cockpit, the prince was in charge of the weapons systems as Apache choppers supported allied troops fighting the Taliban at close quarters and accompanied British and US helicopters on missions to evacuate casualties.

Harry said he would not want to be saddled with the "normal" life of a nine-to-five job.

"I'd never want to be stuck behind a computer desk in the city," he said.

"I don't know what normal is any more and I never really have done.

"There's nothing normal about we've been doing for the last four-and-a-half months.

"In the last day that I was there a seven-year-old girl got shot down by the insurgents. So normality is a very ambiguous thing."

Harry's helicopter instructor meanwhile revealed that the fun-loving prince had once duped French officials into believing he was on a later plane after they failed to recognise him in his uniform.

"The French officer walks up to him -- we were taking our immersion suits off and refuelling the aircraft -- and the officer walked up to him and asked him when Prince Harry would be arriving," Richard Youngs recalled.

"He, quick as a flash, looked back at him and said 'he's on the next aircraft in,' quickly smiled at me, gave me a wink, got back in the cockpit and we flew off," the former Apache squadron commander told ITV television.

The incident happened when an entourage turned up at Le Touquet airport in northern France to greet Harry after a training mission in the French mountains, Youngs said, describing it as his "favourite Harry moment".