Paul J. Ganahl (1916-2002) was an electrical engineer who served in the United States Air Force. This item is a manuscript diary kept by Ganahal between January 2, 1953, and December 31, 1953, while working as an electrical engineer performing aerial photography tests for the United States Air Force in California and New Mexico. The daily entries are bullet lists of film rolls develped, problems found, people met with or spoken to, flight test details, and places traveled. The diary provides technical information about the develpment of reconnaissance photography, engineering challenges, and project team communication.