Splice the mainbrace " Splice the mainbrace " is an order given aboard naval vessels to issue the crew with a drink . Originally an order for one of the most difficult emergency repair jobs aboard a sailing ship , it became a euphemism for authorized celebratory drinking afterward , and then the name of an order to grant the crew an extra ration of rum or grog . History . Braces are the lines that control the angle of the yards . On the first rate men - o - war , the mainbrace was the largest and heaviest of all the running rigging ; the mainbrace on " HMS Victory " is in diameter . Gunners commonly aimed for the ship ' s rigging during naval battles , with the mainbrace being the prime target . If the mainbrace was shot away , it was usually necessary to repair it during the engagement ; the ship was unmanoeuvrable without it and would have to stay on the same tack . Even repairing it after the battle was a difficult job ; the mainbrace ran through blocks , so it could not be repaired with a short splice or a knot . Splicing in a large run of hemp was strenuous work , and generally the ship ' s best Able Seamen were chosen to carry out the task under the supervision of the Bosun ( Boatswain ) . On completion of the task , it was customary for the men to be rewarded with an extra ration of rum . The Bosun would take a sip from the ration of each of the men he had selected for task . Eventually the order " Splice the mainbrace " came to mean that the crew would receive an extra ration of rum , and was issued on special occasions : after victory in battle , the change of a monarch , a royal birth , a royal wedding or an inspection of the fleet . In cases where the whole fleet was to receive the signal , it would be run up with a lift of flags or signalled by semaphore . A ration of rum a day was standard issue in the Royal Navy until 1970 , when concerns over crew members operating machinery under the influence led to the rum ration being abolished . Restrictions were placed on those who could " Splice the mainbrace " : any man or officer over the age of 20 who desired to take it received an extra issue of one - eighth of a pint of rum . Lemonade was issued those who did not wish for the rum . The rum was mixed with water to make grog for all ratings below Petty Officer . Only ratings marked " G " ( for Grog ) in the ship ' s books could draw rum , grog or lemonade when the mainbrace was spliced and no payment in lieu was available . Those under 20 were marked " U . A . " ( for under age ) in the ship ' s book ; they were similarly barred from drawing the daily rum ration . " T " stood for Temperance ( for those of Temperance Movement ) . The issue of rum to Wardroom and Gunroom officer s was stopped in 1881 and ended for Warrant officer s in 1918 ; splicing the mainbrace was the only time that officers could be issued with rum . Other navies abolished the grog allowance far earlier ( the United States Navy after the American Civil War ) , but the order persisted , allowing the crew to take another drink in place of rum or grog ; in 1845 it is recorded as being substituted for the more rowdy " Crossing the Line " ceremony . The Royal New Zealand Navy was the last navy to issue junior and senior ratings a daily tot of rum , issuing its last daily rum ration on 1 March 1990 . Nowadays , the Royal Canadian Navy is more generous with the allowances , allowing crew members to take of spirits compared with the allowed by the Royal Navy , although the Royal Navy does make allowance for paucity of supplies , permitting two cans of beer may be issued if commercial spirits are not available . Permission to issue the order to splice the mainbrace is heavily restricted ; the Royal Navy allows only the Queen , a member of the Royal Family , or the Admiralty Board to do so ; the Royal Canadian Navy permits the Queen , the Governor General of Canada , or the Chief of the Defence Staff to issue it . When the Mediterranean fleet received the order from the Prince of Wales ( the future Edward VIII ) in 1932 it was the first time it had happened since 1918 ; it was accompanied by the order to " Mend and make clothes " , another archaic signal which grants the crew a half - day holiday . Ships in most of the victorious fleets received the order at the end of the Second World War ; one ship received the order while still under attack . King George VI issued the order in 1949 to the crew of the HMS Amethyst after the Yangtse Incident . It was ordered on the day of Queen Elizabeth ' s coronation in 1953 , and of Prince William ' s birth on 21 June 1982 , when " Splice the Mainbrace " was celebrated in the Fleet just one week after the end of the Falklands War . Nowadays , when rum is no longer issued daily , the order is somewhat more freely given ( the Queen issued it after her Golden Jubilee celebrations in 2002 , after the Trafalgar 200 Fleet Review in 2005 , and after her Diamond Jubilee celebrations in 2012 ) . In Canada , the order was most recently given by Queen Elizabeth II on 29 June 2010 at the conclusion of the International Fleet Review for the occasion of the Royal Canadian Navy ' s 100th Anniversary . She signalled : The order " Splice the Mainbrace " was still popular with some of the U . S . Navy ' s submarine fleet during WWII . On the USS " Barb " , a skipper on combat patrols in WWII , during the boat ' s 8th and 9th missions in 1944 , did in fact announce on the 1 MC " Splice the Mainbrace " after each successful attack and sinking of a Japanese ship . On the " Barb " ' s 8th combat patrol , the skipper promised the sinking of 5 ships ; the " Barb " delivered . After each sinking the Skipper had a special cake made and each sailor was granted a shot of rot gut whiskey . On the 9th patrol , the Skipper was able to sneak 24 cases of beer aboard which was distributed after each of the " Barb " ' s successful attacks .