Contains 84 items being minutes, papers, and correspondence covering all stages of the Skybolt airborne missile project from the initial inter-governmental agreement, through technical and financial difficulties, testing, to cancellation of the project. Much of the correspondence concerns the conflicting attitudes towards Skybolt among policy-makers in the United Kingdom and United States. The costs and recurring technical difficulties are referred to frequently as major obstacles so far as the Americans were concerned. SZ was told by one American official that "the technical problems which need to be overcome before Skybolt becomes a reality are formidable" (SZ/CSA/192/27). It was even mooted that, given the difficulties, Skybolt might just continue on a research basis with no operational deployment (SZ/CSA/192/28).

Within British circles there was anxiety that the government should not be embarrassed by cancellation or postponement so soon after obtaining Parliament’s agreement, and if the project were to be cancelled then Britain should be offered an alternative. It was stressed that cancellation would have an adverse effect on Anglo-American relations (SZ/CSA/192/30, SZ/CSA/192/37). SZ believed that it "would be a disaster if the United States does not go on with Skybolt" although he was realistic enough to appreciate that the Americans were sceptical (SZ/CSA/192/64, SZ/CSA/192/77).

As rumours of Skybolt’s cancellation grew, Harold Watkinson attempted to play down the importance of Skybolt. He claimed that it was not "the touchstone of British defence policy" and insisted that development of the Blue Steel missile and the TSR-2 aircraft be continued (SZ/CSA/192/26). Reference is made to the supply of the Polaris submarine-based missile and the provision of a Scottish base for the US Navy. Lord Mountbatten was particularly keen to use the money set aside for Skybolt to buy Polaris and insisted that the "Americans certainly owe us the ability to keep the deterrent going in another form if they deprive us of it through Sky Bolt [sic]" (SZ/CSA/192/38). This was also the view of R.C. Chilver (SZ/CSA/192/63). The cancellation was announced in a minute from the United States embassy in London dated 11.12.63 (SZ/CSA/192/79).

Correspondents include Harold Watkinson, Harold Macmillan, Sir Edward Playfair, Duncan Sandys, Thomas Gates, Sir George Gardiner, L.T.D. Williams, G.V. Fryer, G.H. Mills, Peter Thorneycroft, and David Ormsby Gore. See also File SZ/CSA/88.

SZ visiting the Douglas Aircraft Corporation, Santa Monica, March 1962