Biographical material is substantial. Whittle's career in the RAF is documented by academic notebooks from his years at RAF College Cranwell, RAF College Henlow and the University of Cambridge; two of his flying log books, the earlier covering his flight cadet training at Cranwell, the other containing entries, 1928-1946; Whittle's own accounts of personal experiences such as the 'crazy flying' display at Hendon, and papers detailing a number of his proposed inventions. There is an assemblage of material relating to the history of the turbo-jet including papers and articles by Whittle and a visitors' book for Power Jets Ltd. A large series of diaries and pages of typewritten diary entries spans the years 1927 to 1991. For the years covering the work on the jet engine and the turbo-drill there are, in many places, long and detailed entries concerning technical matters, meetings and foreign trips. There is personal correspondence, 1946-1989, with friends such as Sir Rolf Dudley-Williams and R.G. Voysey and authors of books and articles on the history of aviation, the jet engine etc. Whittle's sporadic involvement in political affairs is also documented by papers, including drafts of articles and speeches relating to his chairmanship of the Migration Council and public addresses at the 1955 (Exeter) and 1964 (Smethwick) General Elections.
Research and Development papers document Whittle's work on the development of the jet engine, his later interests in jet propulsion and jet-powered flight, and the work on the turbo-drill for the oil industry. A series of correspondence and papers, including copies of notes of interviews and meetings etc, reports and technical papers, reflects the day to day involvement of Whittle in the jet engine project from the formation of Power Jets Ltd to the nationalisation of the company. The financial affairs of Power Jets Ltd and the relations between various prominent individuals and companies collaborating in the work are also covered. There is also a series of notebooks in Whittle's hand, 1939-1950, with graphs, calculations and experimental results. The papers concerning his later jet interests are diverse and cover his work for BOAC (1948-1952); a patent infringement case in which he provided expert evidence in support of the defendants, Rolls-Royce Ltd; the problems of 'jet noise'; supersonic aircraft; and a brief consultancy position. A number of his notebooks and sketchbooks, 1973-1993, relate to both jet-powered flight and the turbo-drill. The turbo-drill papers document the various stages of Whittle's involvement: with the Shell Group, Bristol Siddeley Engines and the period following Rolls-Royce's takeover of Bristol Siddeley. There are also small groups of papers relating to Whittle's analysis of possible German submarine development in 1943 and his NAVAIR Research Professorship, 1977-1979.
Whittle's publications are documented by a chronological sequence of drafts for publications and editorial correspondence, 1932-1992. Included is a draft of an early paper on Whittle's turbo-jet idea, dated to 1931 or 1932, entitled 'The Case for the Gas Turbine'. Lectures and broadcasts material covers the period 1943-1987. The jet engine is the chief topic of the lectures, but some relate to the oil industry and supersonic flight. Drafts and notes for lectures include those for his Royal Institution Christmas Lectures on the oil industry, 1954. Broadcasting material is slight but includes correspondence and papers concerning a BBC television programme Jet Propelled, 1966, in which Whittle appeared. Documentation of visits and conferences dates from Whittle's USA visit in 1942 to view American progress on jet propulsion. There are many reports covering his travels while working for BOAC; these give his views on various aspects of civil aviation, including the possibilities for the 'Comet' airliner. He toured the USA on a number of other occasions before his emigration; one of these, in 1974-1975, allowed Whittle to promote Concorde and discuss the possibility of advanced supersonic travel. Societies and organisations material reflects Whittle's associations chiefly with engineering, scientific and learned societies and organisations in the field of aviation, all in Britain or the USA, including the Royal Society, the RAF Technical College and the International Aerospace Hall of Fame.
Whittle's correspondence principally consists of an alphabetical sequence of correspondence with individuals and organisations including M.L. Bramson, Lord Dacre, S.G. Hooker, A. Pouring and the Royal Air Force Museum Hendon, and a chronological sequence of miscellaneous correspondence covering many professional and personal matters 1946-1994. There is also correspondence with inventors who sought Whittle's advice or support, and a small number of 'cranks' letters (Whittle's designation).