RAF Photo Reconnaissance Units (6 colours)

According to preserved copies of official RAF instructions dating back to 1940, aircraft of Photo Reconnaissance Units (P.R.U.) were to be coloured "in accordance with operational requirements", without the need to conform with general RAF standards. First P.R. planes wore overall Camotint Green. Later P.R. Blue (for high-alt missions, officially sanctioned from October 1944, but already widely used from 1941) and P.R. Pink (for low-alt missions / low-clouds-base conditions) were used on most of P.R. planes. One major exception was RAF P.R. planes operating in North Africa and Far East, which used overall Royal Blue instead, as better suited for local conditions.
HTK-AS23 contains a selection of 6 most popular RAF P.R. colours used both on dedicated P.R. aircraft, but also on various high-flying day fighters of RAF.

The set contains:
HTK-A024 - P.R. Pink - Overall colour of RAF P.R. aircraft operating at low altitudes from 1940 (incl. Spitfire PR I) to 1944 (incl. Spitfire FR IX)
HTK-A042 - P.R. Blue - Overall colour of RAF P.R. high-flying aircraft (widely used from 1941). Also on undersides of high-flying day fighters
HTK-A034 - Medium Sea Grey - Used on upper surfaces of RAF high-flying day fighters from May 1943 (including Spitfire Mk VII and Mk IX)
HTK-A025 - Interior Grey-Green - Standard colour of cockpit interiors of RAF aircraft throughout the war
HTK-A051 - Camotint Green - Overall colour of early Photo Reconnaissance Spitfires (converted from Mk I models)
HTK-A055 - Royal Blue - Overall colour of P.R. aircraft in North Africa and Far East incl. Spitfire PR Mk IV, but also Hurricane PR Mk