A sonic boom has been reported across parts of east and southeast England after the RAF deployed aircraft to intercept a passenger plane.
Three Typhoon jets were launched from RAF Coningsby in Lincolnshire on Friday morning to investigate the aircraft, which was not in contact with air traffic control.
Data from flightradar24.com shows one Eurofighter Typhoon FGR4 hitting speeds of just under 700 knots (805mph) at 11.40am.
When it went supersonic, the flight tracking website recorded it travelling at an altitude of around 40,000ft.
People across parts of Kent and Essex reported hearing a loud bang as the fighter jet travelled at supersonic speed.
A Royal Air Force spokesperson said: “We can confirm that RAF Quick Reaction Alert Typhoon fighter aircraft from RAF Coningsby were launched today to investigate a civilian aircraft which was not in contact with air traffic control (ATC), communications were re-established and the aircraft was safely escorted to Stansted.”
Essex Police said: “A flight has been escorted into Stansted Airport after it lost contact with the ground. Our officers determined there was nothing of concern.”
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It is not known what caused the passenger plane, which had been travelling from Nice in the south of France, to stop communicating with ATC.
A sonic boom is caused when planes fly faster than the speed of sound, which at ground level is about 761mph.
The aircraft displaces the air and creates pressure waves that become compressed and are then released in a shockwave.
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The RAF describes the Typhoon FGR4 as a “highly capable and agile combat aircraft” which can be “deployed in a wide range of air operations, including air policing, peacekeeping, and high-intensity conflict”.
