The design and production of the airborne signals intelligence (SIGINT) aircraft of the USAAF during World War Two was an example of a rapid wartime evolutionary process. In three short years, the USAAF went from hand-built prototypes to full scale production of an aircraft type that had not previously existed in the US inventory.Government partnered with universities to form research laboratories focused on radar countermeasures (RCM) while US airline maintenance facilities were requisitioned to form production centres for modifications to allow rapid insertion of the technology. The USAAF pushed the bounds of systems integration and programme management, learning how to rapidly develop, field and operate aircraft in the ever evolving war in the electromagnetic spectrum. Just as the technical design changed, so did the operational employment of these ''ferret'' aircraft. Ferrets started as an adjunct to bombing missions but quickly evolved into aircraft flying their own missions off t