Summary of the report

We describe simultaneous observations of UAPs in daylight by multiple observers (aircrew and passengers) on board two civil aircraft in widely separated locations. Recordings of ATC radar data, and of radio communications reporting events in real time to Air Traffic Control, are examined alongside CAA documents, witness interviews, and other sources. A detailed reconstruction of the sighting geometry is offered. We describe attempts to explain the phenomena with the help of expert advisers and professional resources in the fields of meteorology, atmospheric optics, geophysics and other fields.

It proved possible to eliminate a number of theories with a fairly high level of confidence, but we were unable to conclusively identify the UAPs observed. We found that two theories had some potential to explain at least a majority of the features observed and might be the basis of a future explanation. But we are sensible that a potential to explain is not an explanation.

These two theories involved atmospheric-optical phenomena (specular sun reflections on a haze layer capping a local temperature inversion) or geophysical phenomena (related to "earthquake lights' or EQL). But each theory has some interesting problems. As we state in our Conclusions (Section 7): "It may prove possible for other investigators to adapt these theories and so improve the fit with observation, or further work might thoroughly rule out one or both of them.' A third candidate - a mock-mirage due a severe temperature inversion near the Breton coast - was kept out of contention by one apparently insurmountable problem.

We were able to show that widespread media stories describing enormous phenomena up to a mile wide and detected by radar were based on speculation and misunderstandings. Many news reports were grossly exaggerated and inaccurate. However as we further state:

"We are unable to explain the UAP sightings satisfactorily without either a) discounting at least some significant features of the reports, or b) doing violence to at least some conventional meteorological optics or conventional EQL phenomenology. We hope that readers of this report will find it helpful in deciding which (if either) of those courses of action seems the more reasonable and economical.'