Latest RAF Historical Faux Pas - Envoy IV
Because FGR.7 would suggest a variant of the original Lightning. The correct UK designation following custom and practice would've been something like Lockheed Lightning FG.1. Doubtless Lord West would've demanded it be called the Sea Lightning FA1 or something... (actually, that may be why the US designation was used, to prevent a tedious bunfight over the name amongst retired RN and RAF VSOs - 'Sorry, my Lord, but F-35B Lighting is the correct designation and you'll have to lobby the US about a possible change to Sea Lightning')