NIVO, abbreviated from Night Invisible Varnish Orfordness (or `Night Varnish Orfordness`), was a dark grey-green overall finish applied to British night bomber aircraft in the inter-war period (1918-1939). Developed in 1918 by the Experimental station at Orfordness, as a low-visibility colouring for the Royal Air Force it had a sheen to match th.....