Netherlands Naval Aviation Service The Netherlands Naval Aviation Service ( ; MLD ) is the naval aviation branch of the Royal Netherlands Navy . History . World War I . Although the MLD was formed in 1914 , with the building of a seaplane base at De Mok , Texel , it developed slowly in the inter - war years due to limited budget . After the graduation of the first pilot group in 1915 , on August 18 , 1917 , the MLD was founded under official decree and the De Mok became the main base . At this time , the emphasis was on seaplane operations in the Dutch East Indies where Dornier Wal aircraft enabled patrols of the large archipelago in 1926 . The perceived threat from Nazi Germany in the 1930s accelerated the development of air capability and the purchase of new equipment . World War II . The German invasion of the Netherlands on May 10 , 1940 rapidly overwhelmed Dutch resistance and the MLD aircraft were redeployed to France before the Dutch formally surrendered on 15 May . Shortly after , the MLD was ordered to Britain , where Dutch personnel formed No . 320 Squadron RAF , in Coastal Command , in June 1940 . A second squadron , 321 Squadron , was also formed , but later merged with 320 Squadron . Other MLD personnel served on MAC ships as Fleet Air Arm 860 and 861 squadrons , flying Fairey Swordfish . At this time efforts were made to strengthen the MLD in the Dutch East Indies . When the war started in December 1941 , the MLD numbered 130 airplanes . The main types were 37 each Dornier Do 24 K - 1 flying boats and 36 each Consolidated PBY - 5 Catalina flying boats . The major base was at Naval Air Station Morokrembangan near Soerabaja on eastern Java Island . The MLD had secondary bases as well as seaplane tenders that enabled it to spread out and cover the entire Netherlands East Indies . It was organized into 18 squadrons ( GVT , " Groep Vliegtuigen " ) of about three airplanes each to provide reconnaissance , anti - submarine patrols , convoy escort in support of Dutch forces . The MLD did not have radar . The MLD fought about 95 combat actions , sank one Japanese ship ( destroyer " Shinonome " ) , damaged some others , shot down a few Japanese airplanes and inflicted some casualties on Japanese personnel on the ground . That was not enough to stop the Japanese , and eventually the MLD was forced to evacuate to Ceylon and Australia . They lost 95 % of their aircraft and 50 % of their personnel . On March 3 , 1942 , nine MLD Dornier and Catalina flying boat s were destroyed in the Japanese air attack on Broome , in Australia . About 58 MLD personnel were killed , wounded , or missing . Later that year , on July 1 in Ceylon , 321 Squadron was re - formed under the command of Willem van Prooijen , with MLD Catalinas . The PBYs in Australia were transferred to Ceylon , and the surviving Dorniers were sold to the Australian government . The flight school was relocated to the US . The Royal Netherlands Military Flying School was established in the United States , at Jackson Field ( also known as Hawkins Field ) , Jackson , Mississippi , operating lend - lease aircraft , training all military aircrew for the Netherlands . The intention was to return to the Netherlands and to participate in the war against Japan . After liberation , the main MLD base was established at Valkenburg , with De Kooy as the overhaul and repair base . Post - war . The British escort aircraft carrier was obtained on a two year loan from the Royal Navy and renamed . In March 1948 a light fleet carrier , , was purchased from the Royal Navy to replace the loaned one , and also renamed " Karel Doorman " . Aircraft carried aboard included the fighter - reconnaissance and anti - submarine Fairey Firefly . The main roles of the MLD were maritime patrol , anti - submarine warfare and search and rescue . From 1953 , with the creation of NATO , the MLD received substantial aid from the USA , including PV - 2 Harpoon , P2V Neptune and TBF Avenger aircraft . Squadron 320 and 321 were stationed at NAS Valkenburg and was known as the " group airplanes " . Helicopters were stationed in NAS de Kooy and on ships and were known as the " group helicopters " . Squadron 860 will remain in service and operate the remaining NH - 90 helicopters , but as part of the DHC . In the late 1960s , the aircraft carrier was replaced in the anti - submarine role by a squadron of Westland Wasp helicopter s operated from anti - submarine frigates . These helicopters were replaced by Westland Lynx s and these will be replaced themselves by NH - 90 helicopters . Squadrons 320 and 321 operated Neptunes and the Breguet Atlantic , which were later replaced by the Lockheed P - 3 Orion , the CUP variant . In 2003 , it was announced that NAS Valkenburg would close in 2006 . All Orions were sold to the German and Portuguese Navies . Naval squadrons 320 and 321 were disbanded . In 2008 , the navy helicopters ( Westland Lynx ) and crew of naval squadrons 7 and 860 based at NAS de Kooy were transferred to the defence helicopter command ( DHC ) as were the Dutch air force helicopters . All Dutch military helicopters are now under one single command which is neither navy nor air force . Squadron 7 is to become a small training squadron , squadron 860 will become much larger and is designated DHC ' s maritime squadron with a large navy component . NAS de Kooy was renamed Maritime Airstation de Kooy .