The LVA bought one example unit as a trainer. They wanted a little spicier and brighter version to test for use as a trainer for fighter pilots. It would thereby be used for practising aerobatics.
The LVA version was therefore modified and got both upper and lower wing ailerons and also the tail fin was reduced and also the tail surfaces were modified. The type could now be easier perform in a tailspin
Because of flying upside down behind the engine a little fuel tank was applied to provide the engine inverted flight with fuel. The aircraft made on April 2, 1937 the first flight.
Around the same time for the same purpose a Bücker Bu-131 Jungmann was purchased.
The Koolhoven proved to be inferior, and in mid-1937 it was sold back to Koolhoven, who eventually sold it to the South Sumatra club in Palembang.
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