[3] The prototype, M.F.12 F.14 (V), was the last trainer built for the Royal Norwegian Navy Air Service (RNNAS).

[4] By the late 1930s flying school of the RNNAS requested that a new trainer aircraft be acquired to replace the M.F.8s.

However, as Høver felt that the aircraft seemed to work fine, he made a 20-minute flight, being very pleased with its performance when he landed.

After a rough landing, following drastic and hazardous flying,[6] he demanded that the design be revised to strengthen it before entering production.

[6] The final disposition of the prototype is lost to history, but Høver recalls it being impounded by the German occupation forces,[3] after having been abandoned at Horten on 9 April 1940.