Originally Posted by
Davef68
There is historical precedent for following the manufacturer's numbering, the military DH Herons and Comets were C2 and C4, matching the DH designations (i know it's not exactly the same). but this is a bit American (Texan II, Lightning II, Globemaster III)
Actually the RAF's Herons were C.2, C.3 and C.4 (civil Herons were all Series 1/x or 2/x, the military ones were all equivalent to Series 2).