Chaplains are nominated in different ways in different countries. A military chaplain can be an army-trained soldier with additional theological training or a priest nominated to the army by religious authorities. In the United Kingdom the Ministry of Defence employs chaplains but their authority comes from their sending church. Royal Navy chaplains undertake a 16 week bespoke induction and training course including a short course at Britannia Royal Naval College and specialist fleet time at sea alongside a more experienced chaplain. Naval Chaplains called to service with the Royal Marines undertake a gruelling 5 month long Commando Course, and if successful wear the commandos' Green Beret. British Army chaplains undertake seven weeks training at The Armed Forces Chaplaincy Centre Amport House and The Royal Military Academy Sandhurst. Royal Air Force chaplains must complete 12 weeks Specialist Entrant course at the RAF College Cranwell followed by a Chaplains' Induction Course at Armed Forces Chaplaincy Centre Amport House of a further 2 weeks.