Fleet board is a term in the Royal Navy for the examination cadet officers take which qualifies them to become commissioned officers. After passing the examination, officers who entered as sub-lieutenants have their commissions backdated to the date when they entered the Royal Navy. Midshipmen are also considered commissioned officers at this point, but are not immediately promoted to sub-lieutenant. Between 1955 and 1993, midshipmen were promoted to the rank acting sub-lieutenant after passing the fleet board, but today this rank is only used in the Royal Navy Reserve.[citation needed] After 1955, midshipmen were no longer allowed to serve in the fleet as officers, so in practice they only serve a few weeks as commissioned midshipmen while completing their post-examination training.[citat