LONDON , England ( CNN ) -- British military officials on Sunday said Prince William had not breached any rules when he used a Royal Air Force helicopter to drop in at his girlfriend 's house . Chinhook helicopters are normally used for transporting troops and equipment in war zones . The prince , second in line to the throne , landed a Chinook helicopter -- normally used for transporting troops -- in a field next to the home of Kate Middleton , according to the News of the World tabloid . The paper said the trip had caused fury among some in the military who saw it as a waste of time and money at a time when British forces are thinly-stretched , fighting in Iraq and Afghanistan . The Ministry of Defense said the maneuver was part of a planned training exercise designed to help the prince learn to fly in combat situations . `` Battlefield helicopter crews routinely practice landing in fields and confined spaces away from their airfields as a vital part of their training for operations , '' a statement said . `` These highly honed skills are used daily in conflict zones such as Iraq and Afghanistan . '' The Ministry said that due to a shortage of landing fields available for practice , an offer to land near the Middleton house on April 3 was readily accepted . It said no one got on or off the aircraft , which spent 20 seconds on the ground . Britain 's air forces have already come under criticism for allowing William , 25 , to fly a Chinook to attend a bachelor party , accompanied by his brother , Prince Harry . William , a second lieutenant in the British Army , graduated as a pilot earlier this month following a detachment to the Royal Air Force . E-mail to a friend .
Prince Sultan flew in at Ali 's house using RAF Chinook . Ministry of Defense says it was standard training procedure . Newspaper reports the landing has angered some in the military .