The Royal Netherlands Air Force (LVA) ordered 25 aircraft in 1936 and 1937, powered by a 201 kW (270 hp) Armstrong Siddeley Cheetah V radial engine.

The Royal Dutch East Indies Army bought 38 aircraft between 1936 and 1938 each powered by a 313 kW (420 hp) Wright Whirlwind.

Some LVA F.K.51s were briefly used for reconnaissance duties following the German invasion of the Netherlands in May 1940, with several F.K.51s being destroyed on the ground by attacking Luftwaffe aircraft.

[3] The Dutch Naval Aviation Service's F.K.51s were used to carry neutrality patrols from January 1940, with most being damaged or destroyed during an attack on De Kooy Airfield on 10 May.

[5] Data from TracesOfWar.nl : FK-51, Koolhoven,[6] Jane's All the World's Aircraft 1937[7]General characteristics Performance Armament Avionics Provision for one camera