Of the 50 aircraft ordered in the Netherlands by the French state, 40 were manufactured. 
               
                The first 4 aircrafts delivered in emergency, were equipped disaster 
                of the engine Hispano Suiza 14 AA 10. The following, equipped 
                with the good engine, the Rhone Gnome, were first delivered by 
                air, then, to simplify deliveries, Is decided to deliver the aircraft 
                dismantled by boat to the port of Le Havre, and then to assembly 
                to Nevers.
              In fact, 40 Koolhoven were manufactured, but they remained in parts at Nevers. One of these 23 was finally completed. 
              
            In 
              total, only 14 aircraft were taken into account by the Air Force 
              which refused the first 4 delivered with a Hispano engine.
           
           
              France, in 1938, 
                try to replace his outdated fighters. Given that the national 
                industry has not been able to fill the gaps itself, it is logically 
                towards the United States and the Netherlands that France turns 
                . England, for her part, is too busy modernizing herself to furnish 
                aircrafts outside the kingdom.
              In the Netherlands, the company Fokker is already occupied with national orders (Fokker DXXI and Fokker G1) and only the company Koolhoven is ready to meet the French demand. The project of Koolhoven, called Model 1166, then FK 58 (58th model of the mark), is developed in only three months. The fuselage of the FK58 is made of steel tubes covered at the rear and covered with Duralumin plates at the front. The wings are classic, wood covered with plywood. The selected engine is a Rhône 14N39 Gnome of 1100 CV at take-off.
              The prototype made 
                its first flight on July 17, 1938. The tests are conclusive and 
                a second prototype is launched quickly with slight modifications. 
                Serial production is planned before even having an official order. 
                The prototype is conveyed by air to France. It receives a civil 
                registration in order to allow it to fly over Belgium, still neutral 
                in October 1938. The tests at the CEMA of Villacoublay (Center 
                Experimentation of the Air Equipment) highlight a speed Low Maximum: 
                the 448 km / h reached are far from the 500km / h of the initial 
                specifications. The aircraft is however manageable and its time 
                of rise to 8000m is better than that of Morane MS406. The plane 
                is presented at the Air Show, with an advertisement for the least 
                optimistic. The official order finally passed in January 1939 
                for 50 aircraft to replace the Potez 25 in service in Indochina, 
                and equip two of the three fighter squadrons present in the Far 
                East.
              The first 4 serial 
                deliveries delivered to the CRAS (Series Aircraft Reception Center) 
                are in fact equipped with Hispano-Suiza 14AA 10 engine with Dutch 
                civilian registrations. The following FK58s are first delivered 
                by air, the others to be delivered by boat and assembled at Nevers. 
                In December 1939, the situation was as follows: 40 FK58 were delivered, 
                and 23 were still parts in Nevers. Only one of them will be completed. 
                The Air Force also refused the first four FK58 equipped with Hispano-Suiza 
                engines. These engines, which are heavy, have a low output: 24.7 
                hp / liters compared to 30.5 hp / liters for the Rhône Gnome, 
                and thus degrade performance already very average ... So it received 
                14 troops allocated it to squadrons Of Defense, piloted mainly 
                by Polish pilots. Three FK 58 will serve as part of the Caen-Carpiquet 
                patrol, two other patrols based in Salon de Provence were equipped 
                with this poor fighter who fought until June 5, when they were 
                evacuated to Toulouse and Clermont-Aulnat
              The survivors are 
                quickly frightened after the Armistice, and a exemplary is recovered 
                by the Germans.