01/31/2012. Remarks by Johan Visschedijk: "Pictured on a flight from Heathrow, this aircraft was one of the first batch of 200 F.Mk.I aircraft (s/n in the range Z1826 to Z2126), which included several prototypes:

Z1826 to Z1829 F.Mk.I, prototypes, Z1826 later FR.Mk.I prototype
Z1831 G.Mk.II prototype
Z1835 F.Mk.III prototype
Z1875 NF.Mk.II prototype
Z1901 FR.Mk.IA prototype
Z2118 F.Mk.IV prototype"