http://avherald.com/h?article=4d0f19f9&opt=0Incident: United B764 over France on Dec 20th 2019, loss com invokes supersonic boom
A United Boeing 767-400, registration N78060 performing flight UA-121 from Barcelona,SP (Spain) to Newark,NJ (USA),
was enroute at FL300 over France when the crew did not contact/respond to French Air Traffic Control
for considerable time after crossing from Spanish into French Airspace.
French Rafale fighter aircraft were dispatched at about 10:40Z
to intercept the aircraft causing sonic booms enroute to the rendezvous.