LONDON (AFP) – Britain's Prince William will begin training to become a search and rescue helicopter pilot on Monday, embarking on a new stage of his military career that will bring him as close as possible to the action.

The 26-year-old, who is second in line to the throne after his father Prince Charles, will learn to fly Sea King helicopters in treacherous conditions to rescue stranded sailors or mountaineers in trouble.

William was an officer in the army but it was deemed too dangerous to send him to Afghanistan with his unit last year. A new path opened up after he spent four months with the Royal Air Force, and decided to transfer.

"The time I spent with the RAF earlier this year made me realise how much I love flying," he said in September.

"Joining search and rescue is a perfect opportunity for me to serve in the forces operationally, while contributing to a vital part of the country's emergency services."

His new commanding officers warned the prince will not get preferential treatment during the training course, which will last between 18 and 20 months and from which he should emerge as an operational pilot.

William must then complete at least one three-year tour of duty, on an annual salary of 36,000 pounds (55,000 dollars, 40,000 euros).

"We put them under a lot of pressure and expect a lot of them," said Group Captain David Prowse, station commander of RAF Shawbury in Shropshire, central England, where the prince will do most of his training.

"Because after all, once they leave they could find themselves low level, at night, in a Sea King, in bad weather trying to get somebody to hospital or trying to get them off the hills."

The RAF search and rescue force operates 24 hours a day in Britain, Cyprus and the Falkland Islands. Its main role is to recover RAF personnel but in peacetime it mostly responds to civilian incidents -- 1,000 a year on average.

Emergencies range between rescuing lost hill walkers to dealing with natural disasters such as flooding, with the four crew members on board each Sea King trained to work in tough weather conditions.

William, the eldest son of Prince Charles and the late princess Diana, will continue to be involved in royal duties while training, and has about 20 events planned over the next 12 months, similar to last year.