The George Knox Roth Collection (1959-1980) consists of newspaper clippings (including photocopies), magazine articles, newsletters, technical reports and publications, correspondence, notes, and photographs relating to the Atomic Energy Commission, the environmental impact of nuclear testing in Nevada, Nevada mining, Airwest and the Hughes Airport, and other aspects of Howard Hughes’ Nevada operations. The George Knox Roth Collection also includes correspondence and expense reports related to his own company, General Research Consultants.

The Bob McCaffery Collection on the Save the Hughes Flying Boat Campaign (1980-1983) documents efforts by activists to preserve the plane from destruction and its subsequent acquisition by the Aero Club of Southern California in 1980. The collection contains photographs and newspaper clippings about the Hughes H-4 Hercules flying boat nicknamed the "Spruce Goose" from the 1980s.