DI55 (Defence Intelligence).
official-recordinstitutionRendlesham Forest (RAF Bentwaters/Woodbridge)
Secretive Defence Intelligence Staff branch (within the Directorate of Scientific and Technical Intelligence) that quietly collected UFO sighting data and commissioned the Project Condign study.
DI55's primary role was ballistic-missile/space-vehicle intelligence, which is why UFO handling was routed to it. It secretly gathered ~10,000 sightings (officially from 1967 to 2000) and commissioned the 1997–2000 Project Condign report. David Clarke argues, citing a 1998 internal minute, that Condign partly served to extract DI55 from UAP monitoring; DI55 ceased UFO work at the end of 2000, with the public UFO desk following in 2009.