Mirage IV encounter with unidentified aerial object — Dijon/Luxeuil, France

On March 7, 1977 at approximately 2100 local time, Mirage IV pilot Herve Giraud and his navigator observed two successive bright glowing objects (designated A1 and A2) approaching on a collision course during a return flight to Luxeuil at altitude 9600m and Mach 0.9. A1 maneuvered behind the Mirage despite a 3-4g bank to maintain visual contact. A2 subsequently appeared and required a 6.5g bank to disengage. Neither object was detected on the Contrexeville military radar. No sonic boom was heard despite apparent supersonic maneuvering capability. The objects demonstrated performance exceeding any known combat aircraft.

“Only a combat aircraft could have had performance comparable to that of A1 and A2 (speed, maneuverability). In this case, C would have had a radar contact on this aircraft... their speed could only be supersonic, which, in the case of combat aircraft, would be manifested on the ground by a very loud sonic boom... But no sound was heard in the region.”

Source is the COMETA report (French association, 1999), translated into English. This is a secondary analytical document summarizing cases; primary CNES/SEPRA records are referenced. The COMETA report was produced by former French military and defense officials. Confidence reflects quality of sourcing and corroboration.