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Bubble Sextant

Catalogue number:
AF*59068-N

Inscriptions:
"A.M. BUBBLE SEXTANT MK IXA REF N^O 6B / 218 BRIT PATS 480112 490621 AND PENDING" and "A.M. SERIAL N^O 761 / 43"

Discussion:
This instrument, introduced in 1938 and widely used by the Royal Air Force during World War II, is a modification of the Booth sextant designed by the British Royal Aircraft Establishment in 1918. Its most important new feature is a mechanical device that gives the navigator the average value of 60 observations taken over the course of two minutes. It was probably made by Hughes & Son, Ltd., of London. "A.M." refers to Air Ministry. P.V.H. Weems donated this example to the Smithsonian in 1963.

Ref: Peter Ifland, Taking the Stars (Newport News, 1998), pp. 167-170.

Francis Chichester, The Observer’s Book on Astro-Navigation.

Further Information:

Hughes
Aircraft Sextant