Find British military officers in the three services in their respective lists now available on the Internet Archive (Texts). Most cover the period of the two world wars, and are digitized from the National Library of Scotland. A few earlier issues are available, mostly from the University of Michigan.
Air Force List, available from 1919 to 1945, 59 issues includes civilians associated with the military, meteorologists for instance.
Navy List, available from 1914 to 1945, 122 issues with a few additional issues as early as 1849.
via Chris Paton at http://goo.gl/7KXfX who lists some other NLS finds.