Dept. of DefenseUnresolvedAnomalous kinematics

Lakenheath-Bentwaters UFO — UK, multiple radar and visual contacts

Aug 13, 1956Lakenheath and Bentwaters, Suffolk, UK3,937 ft

Analysis — our summary

On the night of August 13-14, 1956, USAF and RAF radar at Bentwaters detected an object moving east to west at 2000-4000 mph. Ground and airborne visual sightings corroborated the radar returns. A stationary object was then tracked at Lakenheath before accelerating to 600-950 km/h and performing abrupt direction changes and stops. An RAF Venom fighter was guided to the object, locked it on radar, then lost it as the object positioned itself behind the fighter for approximately 10 minutes despite all evasive maneuvers. The Condon Commission's radar expert later called it 'certainly one of the most disturbing UFO incidents known today.'

As reported — verbatim from the document

“The fact that radar and ground visual observations were made on its rapid acceleration and abrupt stop certainly lend credence to the report. ...the pilot tried every maneuver for about 10 minutes in order to move back behind the object (steep climbs, dives, sustained turns), but he didn't succeed: the UFO followed him at a constant distance.”

Analyst notes — caveats & confidence

Source is COMETA 1999 analytical report, itself based on Condon Commission records and Thayer's 1971 Astronautics and Aeronautics article. Classified as unresolved by the Condon Commission. Klass challenged the interpretation in 1976; those challenges were subsequently contested by other researchers.

Provenance

Source document255_413270_UFO's_and_Defense_What_Should_we_Prepare_For.pdf

Document typeanalytical report

Reporting agencyDept. of Defense

Source pages94

DeclassifiedFirst public at this release (2026)

Held classified~70 years (≥, to this release)

Extraction confidence HighHow cleanly this record could be parsed from the source — driven by legibility & redaction. It is not a measure of how credible or anomalous the sighting is.