and of course changing from the Dutch LVA's 7.9mm FN-Brownings to 7.7mm Brownings.
Did I say they were??? The design was for the LVA fitment using 7.9mm FN-Brownings. VL amended the design to mount 7.7mm Brownings for Finnish production and service - Fokker didn't make the changes. What is unclear about what I said?No Dutch guns nor guns of that caliber were fitted to Finnish Fokker DXXI.
Actually - the Finnish-built Mercury D.XXI Series I and Series II aircraft - two batches, 14 and 21 - had four Vickers 7.7mm MGs - two in the fuselage, ONE in each wing - but fitting the two-row Twin Wasp meant the fuselage fitment was not longer possible - which is why VL amended the wing fitment to TWO 7.7mm Brownings per wing instead.