Over three nights in December 1980, USAF personnel at RAF Woodbridge, Suffolk, encountered a structured craft in Rendlesham Forest. Deputy base commander Lt. Col. Charles Halt documented the events in a memo to the UK Ministry of Defence and captured audio of a second encounter on microcassette.

On December 26, USAF Sgt. Jim Penniston, A1C John Burroughs, and A1C Ed Cabansag responded to lights descending into the forest. Penniston reported touching the craft's surface. Two nights later, Halt led a larger team and recorded objects maneuvering overhead and firing beams toward the ground. The Halt Memo (January 13, 1981) remained classified until 1983. MoD file DEFE 24/1948 is held at the UK National Archives.