The 27-year-old army captain, who spent 10 weeks on the front line in 2007/08, will be in the hot seat of a fearsome Apache during his four-month deployment.

Having arrived in the war-torn country in the early hours of today under the cover of darkness, Harry spent his first morning at Camp Bastion checking over the state-of-the-art Army aircraft he has likened to a "robot".

He looked relaxed, if slightly tired, and gave a thumbs-up after a long journey on a troop flight from RAF Brize Norton in Oxfordshire.

The royal climbed up to peer into the cockpit of one of the helicopters he will fly and crouched down to inspect its weapons.

He wore his combat uniform and was joined on the Apache inspection by another unnamed member of the 100-strong unit he is posted to, 662 Squadron, 3 Regiment Army Air Corps.

After about 10 days of acclimatisation and training, Captain Harry Wales – as he is known in the Army – will go on operations in his role as co-pilot gunner.

The Queen and Prince of Wales were both fully briefed about the move. Charles is "immensely proud of his son", St James's Palace said.

The spokesman added: "He's approached the deployment with a range of emotions like any other soldier and feels pride and anticipation as he deploys."

Harry can put his naked Las Vegas romp behind him, and his antics can be seen as letting off steam ahead of a taxing deployment.

Harry was a second lieutenant with his regiment, the Household Cavalry, for his first deployment to Afghanistan and worked as a forward air controller co-ordinating air strikes on Taliban positions.

During his current posting he could carry out similar tasks to those he co-ordinated in 2007/08.

That tour of duty was abruptly ended when foreign media broke a news blackout on reporting his service.

This time the Ministry of Defence has chosen to confirm this move after a threat assessment concluded that acknowledging his presence in Afghanistan would not put the royal or his colleagues at further risk.

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