WINTERBOTHAM, FRED• 583and head its new Air Section, which was intended to liaise closely
with several of his old colleagues in the Air Ministry’s tiny intelli-
gence branch. During the next eight years, Winterbotham made nu-
merous visits to Germany, often piloting himself, recruiting sources,
and making clandestine photographic reconnaissance flights over
sensitive airfields. In 1939 he commissioned another pilot, Sidney
Cotton, to undertake to verify the Siegfried Line for the Deuxie`me
Bureau, and Wilhelmshaven for the Admiralty.
After the outbreak of World War II, Winterbotham’s section took
over responsibility for the secure distribution of the signals intelli-
gence product that, in 1941, was to become known asultra. Winter-
botham’s task was to ensure summaries of the decrypts were
conveyed fromBletchley Parkto selected military commanders
using a dedicated communications channel of specially indoctrinated
liaison officers equipped withone-time padsand the latest crypto-
graphic technology. These three-man teams, discreetly attached to in-
dividual theater staffs, were known asSpecial Liaison Units, but
very few knew their true function.
Winterbotham’s achievement in obtaining interservice coopera-
tion at Bletchley Park was not without its pitfalls. Thedirector of
naval intelligence(DNI), for one, proved awkward to deal with, the
blame for which Winterbotham placed on the DNI’s assistant,Ian
Fleming. But if he was critical of Fleming, he was full of praise for
the colleague he described as his ‘‘scientific assistant,’’R. V. Jones.
The security surrounding the Allied codebreakers was such that no
word of the success they achieved leaked until an American journal-
ist, Anthony Cave Brown, discovered in 1972 that Bletchley’s boffins
had accomplished far more than had hitherto been suspected or hin-
ted at. While a few participants had known of their particular contri-
bution, only a relative handful of the 10,000 employed byGCHQ
gained an overall view ofultra’s astonishing scope. One of those
was Winterbotham, who, when challenged by Cave Brown to dis-
close what he knew, approached the authorities for permission to
publish his own recollections.
Winterbotham had at this stage already released a suitably sani-
tized account of his experiences,Secret and Personal, published in
1969, which carefully omitted any reference toultra. The author’s
announcement that he proposed to release a comprehensive version