There is also ‘A History of Martinsyde Aircraft’ by J.M.Bruce, which was published in The Aeronautical Journal of the Royal Aeronautical Society, Vol. 72 No. 693 September 1968. I’ve taken a look at the copy which Schneiderman kindly supplied to me a couple of years ago but it contains no images of G-ABKH. However there is a reasonably sharp 1931 image of the A.V.1 in ‘British Civil Aircraft’ by A.J.Jackson, 2nd ed. Vol III p.32. Although, obviously, that is monochrome, using that and extrapolating from what Roel says about the colour scheme, I would suggest the following;

– white upper fuselage and top surfaces of mainplanes and tailplanes
– lighter blue cheat line
– darker blue lower fuselage
– white (or pale colour) registration mark on lower rear fuselage

Jackson describes it as “resplendent in two vivid shades of blue”. The fin and rudder are painted with a rather 1960ish wavy ‘raspberry ripple’ design, which looks to be the aforementioned white, darker blue and lighter blue in three repeated anti-clockwise sequences. On the lower fuselage, beneath the front cockpit is a stylised circular motif in the same colour as the registration mark. Jackson says that the stylised letters within the circle are CAV, the initials of its owner, C. Amherst Villiers.