BISN.

The BI flag is a white burgee with a red St Andrew’s cross. Accounts of a flagmaker misunderstanding Scottish instructions are explicitly unauthenticated and differ: one says blue was intended, another white on blue mistaken for St Patrick’s red on white. Saltire width and distance from the fork vary. Brown 1940 is described with arms 3:14 of the hoist and a white border 4:14, the observer questioning the relative widths. Larousse 1930 gives an approximately quarter-depth fork and saltire arms about one-quarter of flag height. Rosanoski rejects versions taking the saltire to the fly points. The National Maritime Museum specimen, dated about 1951, measures 1676.4 × 2590.8 mm; another actual flag offered in 2006 measured 67 × 116 cm.

Film and monochrome photographs show a very narrow gap between the two white bands on the black funnel, identified as a funnel hoop. The accompanying livery account gives black hulls with a narrow white band, red boot-topping and stone-coloured kingposts and topmasts. Passenger ships received white hulls with a black line from 1955.

Troopships are described with buff funnels and white hulls with a dark-blue band. B117 is attributed to Dunera and Nevasa as passenger, school and cadet ships available for troop service, but Rosanoski expressly says Ocean Ships 1967 disproves the Nevasa attribution.

The fleet commodore’s flag adds a red ball in the white hoist area. It was first flown by Captain Carre aboard Rohanna in Penang Harbour in 1926. After fleet absorption, the cadet ship Uganda alone continued to fly the flag. The museum specimen, dated about 1951, measures 939.8 × 1320.8 mm.