Flat - iron gunboat Flat - iron gunboats ( more formally known as Rendel gunboats ) were a number of classes of coastal gunboats generally characterised by small size , low freeboard and the absence of masts . They acquired their nickname from the physical similarity with the flat iron used for ironing clothes during the 19th century . The first flat - iron gunboat was launched in 1867 , and the last in 1894 , with the vast majority being built in the years 1870 - 1880 . They were designed as a cheap coastal defence weapon , a role they failed to achieve successfully ; they found their greatest utility in offensive coastal bombardment . Strongly built , they lasted in some cases into the late 20th century , and saw action in both World Wars . The hull of the British flat - iron " Medway " lies in shallow water off Bermuda , and the Norwegian flat - iron " Tyr " was afloat as recently as October 2009 under the name " Bjorn West " . Origin . In 1867 Sir W G Armstrong & Company signed an agreement with a local shipbuilder , Dr . Charles Mitchell , whereby Mitchell ’ s shipyard would build warships and Armstrong ’ s company would provide the armaments . George Rendel was put in charge of the new venture , and the vessels designed under his leadership were based on a small craft used by the Armstrong factory to test heavy guns . With the assistance of the leading gunnery expert Admiral Sir Astley Cooper - Key , he turned these craft into a gunboat designed for defensive coastal operations . Description . A typical flat - iron gunboat displaced about 250 tons , had a length of less than and drew only . It was armed with a single large gun ( normally 10 to 12 inches , but in the case of the Italian " Castore " class , a massive 16 - inch weapon ) . The gun , which was mounted at the bow , was designed to be raised and lowered on a hydraulic mechanism so that stability would not be compromised when making sea passages . The gun was aimed by pointing the whole vessel , since the mounting allowed for elevation but not traversing ( in the manner of an enormous punt gun ) . No rigging of any sort was provided , and twin screws were fitted , allowing for a much reduced draught while at the same time making them highly manoeuvrable . Top speed would have been less than , but they were designed to be towed at considerably higher speeds than they were capable of making under their own power . The crew would have numbered about 30 men . Larger variations were built , with the German " Wespe " class displacing as much as 1 , 157 tons . Masted versions were produced , particularly for navies with inadequate coaling facilities and long coastlines , and commensurate with an increase in displacement , armament and rigging , crews increased to match , with the " Wespe " class needing 76 men . The original design was intended for defensive coastal operations , but was employed by the Royal Navy largely for offensive coastal bombardment , and in this sense was a natural successor to the Crimean gunboats of the " Great Armament " and the bomb vessel s of the Napoleonic Wars . Operations of this nature require command of the sea , a situation which the Royal Navy could impose by virtue of its battlefleet throughout the period . Few other navies of the time could hope to exercise much more than local sea control for limited periods , and these vessels were of limited use for shore bombardment in the hands of smaller or less effective operators . Nevertheless , these small vessels with their powerful punch were clearly attractive to the small and medium - size navies of the late 19th century , since they offered the status of big guns without the price tag associated with contemporary cruisers and battleships . This may account for some of the later vessels carrying monstrous 15 - and 16 - inch guns ; flat - irons armed in this fashion were not long lived , probably because their weapons were all but useless except in a flat calm , and none at all against a moving target . The defining failure of flat - iron gunboats as coastal defence weapons was in China , where British - built gunboats were used against both the French ( at the Battle of Fuzhou ) and the Japanese ( at the Battle of Weihaiwei ) . In general the flat - iron gunboats found themselves outmanoeuvred and smothered by shellfire from the more stable enemy cruisers ; many failed to get off more than one or two shots . In contrast to their failure as coastal defence gunboats , the occasions when they were used for coastal bombardment were more successful ; Argentinian gunboats were used in 1890 to bombard rebels during the Revolution of the Park , Greek gunboats bombarded Turkish forces during the Greco - Turkish War of 1897 and both " Bustard " and " Excellent " ( the former HMS " Handy " ) were part of the force that bombarded the Belgian coast during World War I . Professor Andrew Lambert argues that the Royal Navy flat - irons succeeded in their task of deterrence , and that they were a key asset to the capability of coastal offensive operations . Operators . Australia . The Australian colonies of the British Empire purchased a number of gunboats for coastal defence during the 1880s , and while they were described as " flat - irons " , they were masted and " Protector " was almost the size of a light cruiser . The remains of both " Protector " and " Gayundah " remain visible today . Argentina . Argentina purchased four flat - iron gunboats from Laird Brothers , Birkenhead and J & G Rennie & Co , Greenwich , in 1875 . Described as " bombarderas " ( literally : bombers ) in Argentina , they were variously employed in later life as tankers , transports and pontoons , lasting in some cases into the 1950s . Chile . The Chilean government entered into talks to purchase two vessels similar to the Argentinian units , but did not see the purchase through . China . Between 1875 and 1880 China purchased 13 flat - iron gunboats from Britain and built another ( " Tiong Sing " ) at Shanghai . After the two " Jiansheng " class , the British - built boats were given names from the Greek alphabet , from " Alpha " through to " Lambda " , thus becoming known as the " alphabetical " gunboats . Although quickly given Chinese names , the class names seem to have stuck . A further pseudo - Rendel gunboat ( " Hoi Tung Hung " ) was built locally to the lines of the " alphabetical " flat - irons , but constructed from wood sheathed in iron . " Fusheng " and " Jiansheng " were lost in the Battle of Fuzhou in 1884 at the beginning of the Sino - French War . Four Chinese Rendel gunboats also took part in the Battle of the Yalu River against the Japanese in 1894 . Eight Chinese flat - iron gunboats were sunk or captured by Japan at the battle of Weihaiwei in 1895 . Denmark . Five boats in three classes were built in Danish shipyards in 1874 to 1876 . Three were decommissioned at the turn of the 20th century and the other two were decommissioned after World War I having served as repair ships . Germany . The German Navy ( " Kaiserliche Marine " ) built eleven large Rendel gunboats ( " Panzerkanonenboot " ) of the " Wespe " class at AG Weser , Bremen between 1875 and 1881 . One , SMS " Salamander " , was lost in 1910 . Two smaller gunboats of " Brummer " class were built later in 1884 . Greece . In 1881 Greece had 2 Rendel gunboats built at the Thames Ironworks and Shipbuilding Company for the shallow waters of the Ambracian Gulf . They saw action in the Greco - Turkish War of 1897 and Balkan Wars , served the Piraeus and Keratsini net barrage during World War I and were scrapped after World War I . Italy . Italy built two Rendel gunboats at Spezia Dockyard in 1874 . In the late 1880s 2 large Rendel gunboats were designed and built by Armstrong Mitchell & Co . ' s Elswick Works to a contract by the Italian War Ministry . They were constructed in Elswick ' s Tyneside yard in the United Kingdom , disassembled and shipped to Italy for reassembly in the Armstrong facility at Pozzuoli . Japan . Japan captured 6 Rendel gunboats from China on 12 February 1895 at the Battle of Weihaiwei . They were listed for disposal in 1906 and broken up by 1907 . Mexico . Two gunboats were commissioned from Armstrongs in 1875 , but appear to have been heavily - sparred , single - screw iron gunboats with an extensive sail area . Their short , broad dimensions and single large gun cause them to be confused for flat - irons , but illustrations show that they are not of the same type . They were scrapped in 1920 . Netherlands . Thirty - one flat - iron gunboats were built in the Dutch shipyards Christie , Nolet & De Kuyper and Feijenoord Mij in the years 1870 to 1880 . " Vahalis " and the " Hydra " class were nearly all decommissioned before World War II ( " Sperwer " was retained until 1960 as a training ship , and " Brak " sank in 1902 ) . Ten of the " Wodan " class lasted long enough to be sunk or captured by the advancing German army in 1940 . Norway . Eight flat - iron gunboats were built to a British design in Norwegian shipyards . They were all refitted as minelayers before World war I . " Æger " was decommissioned in 1932 , but the others were all captured by Germany in 1940 and with the exception of " Uller " they survived WWII . Gradually decommissioned by the Royal Norwegian Navy after World War II , nevertheless , the " Gor " - class gunboat " Tyr " was still operating as the civilian ferry " Bjørn West " 100 years after she was built . Russia . Russia built ten Rendel gunboats in three classes between 1874 and 1881 . Two " Sivutch " - class gunboats were also constructed which had a brig rig ( later replaced by a ship rig , and later still de - rigged ) . They were armed with a single 9 - inch gun and a single 6 - inch gun aft . Visually they were very similar to the British " Medina " class . Sweden . Sweden built 10 Rendel gunboats in Stockholm and Norrköping between 1868 and 1876 . United Kingdom . The Royal Navy had two classes of flat - iron gunboats built in the 1870s and 1880s , as well as several one - off prototypes . As built they were equipped with a single 9 - inch or 10 - inch gun muzzle - loading rifled gun ( MLR ) . Their sound construction meant that many stayed in service in support roles with a number ending up as gunnery tenders , lighters , tank vessels and dredgers . One notable gunnery tender was " Bustard " which went on to be rearmed prior to World War One . During World War I " Bustard " , " Drudge " and " Handy " ( renamed " Excellent " from 1891 ) , and possibly " Mastiff " ( renamed " Snapper " in 1914 ) and " Ant " , took part in a bombardment of the Belgian coast . The majority of the flat - iron gunboats had been scrapped before the mid - 20th century but " Handy " survived until she was broken up in 2008 amid safety concerns . For many years it has been assumed that the Royal Navy flat - irons were a failure at their perceived role of coastal defence . Professor Andrew Lambert has more recently argued powerfully that they were designed for coastal assault as successors to the gunboats of the Crimean War " Great Armament " , and that they succeeded in their deterrence role . He describes them as a " part of a sophisticated , layered approach to the tactical problem of defeating large - scale coastal defence systems . " The Royal Navy listed them as " Gunboats for the Attack and Defence of Coasts " in its confidential Pink List . Their lack of speed and limited armament left them of little value in defence of a coast or harbour , but they were ideally suited for bombardment of shore fortifications in a situation where the Royal Navy enjoyed complete command of the sea . " Staunch " and " Plucky " were essentially prototypes built in 1867 and 1870 . " Handy " and " Drudge " were built in the 1880s for testing the mounting of 13 . 5 - inch guns intended for the " Royal Sovereign " - class battleships . The " Medina " class were a development of the flat - iron concept which resulted in an iron coastal gunboat fitted with three masts and carrying three 6 . 3 - inch 64 - pounder rifled muzzle - loading guns . The naval historian Anthony Preston described them as " the most grotesque craft ever seen " . The hull of " Medway " remains visible on satellite imagery at .