Spitfires Mk I of No. 19 Squadron RAF at Duxford May 1939
In October 1938, when No. 19 Squadron RAF displayed its Spitfires to the press, the aircraft featured one of two disruptive camouflage schemes of Dark Green and Dark Earth on the upper surfaces, with aluminium undersurfaces. The roundels used on the aircraft were Type A1 on the upper wings (56 inches in diameter) and fuselage (34 inches in diameter). On the lower surfaces of the wings, Type A roundels measuring 50 inches were applied. The aircraft serial numbers were painted in 12-inch high digits, with the serial on the starboard wing appearing upright when viewed from head-on, while that on the port wing appeared upside down. Additionally, an 8-inch high black serial number was placed on the rear fuselage. During this time, fin flashes were not applied, but No. 19 Squadron briefly painted its squadron number on the fin in flight colors (red for A Flight, blue for B Flight, yellow for C Flight, and green for D Flight). The spinner was black.
The camouflage patterns used on these early Spitfires were referred to as the ‘A’ and ‘B’ schemes, with the ‘B’ scheme being a mirror image of the ‘A’ scheme. Generally, aircraft with even-numbered serials had the ‘A’ scheme, while odd-numbered serials had the ‘B’ scheme, although exceptions did occur. Both schemes were used until December 1940, when the ‘A’ scheme was standardized.
Towards the end of 1938, the undersurfaces were repainted with a 50/50 split of black and white. The ailerons were painted in the opposite color to the wing they were on (e.g., a white wing would have a black aileron). The dividing line was along the fuselage centerline. In March 1939, an order was issued to replace the wing and fuselage roundels with the blue and red Type B roundels, and squadron code letters appeared for the first time. This system identified the squadron with two letters and individual aircraft with an additional single letter.
Around the same time, the undersurface scheme was revised. While the port side remained black and the starboard white, the opposing-colored ailerons were removed. The lower rear fuselage and chin cowling returned to being aluminium. Serials were sometimes displayed in black on white or white on black. Aircraft with aluminium undersurfaces were repainted at the squadron level, with the port side often painted first, resulting in an appearance similar to the black and white scheme.
By December 1939, the fuselage roundel was switched to Type A, which remained in use until May 1940 when it was replaced with the Type A1 roundel with a yellow surround for operational aircraft. In the same month, fin flashes were introduced on Spitfires for the first time.