The RAF has confirmed it launched fighter jets over London today (Friday, August 15) to investigate a plane, understood to be travelling from Nice in France, which had to be escorted to Stansted Airport. The decision to approve the Quick Reaction Alert is what caused the sonic boom ‘bang’ heard over many parts of London and Essex.
A Royal Air Force spokesperson confirmed: “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, communications were re-established and the aircraft was safely escorted to Stansted. The Typhoons are returning to base.”
The spokesperson added the RAF regrets any inconvenience caused after residents in London were alarmed by a sonic boom linked to the deployment of Typhoon aircrafts. A spokesperson for the East of England Ambulance Service Trust said: “We were alerted to a potential emergency with an incoming aeroplane at Stansted this morning and sent resources in line with our standard procedures. The plane landed safely and the incident was stood down.”
Javelin Sam (@javelinsam) on X posted at 11.46am: “Sonic boom just heard over Hornchurch. Eurofighter Typhoon FGR4 went overhead.”
It was also heard in Essex with @losing_focus posting on X at the same time: “Anyone else just hear a sonic boom over South Essex?” Replies included from users who said it “shook my house” and “heard a bang in Braintree. Loud enough for people to go outside to have a look.”
@jsphsilver added: “YES shook my bloody flat. Definitely was the typhoon.”
What exactly is a sonic boom and why does it occur?
A sonic boom is the sound associated with the speed of sound being broken. Shock waves are created when an object, in this case the fighter jets, travels through the air faster than sound.
This creates an enormous amount of sound energy. To the human ear it sounds like an explosion or a thunderclap. Due to the size of the aircraft this can be particularly loud and startling. As a result of the impact aircrafts are prohibited from supersonic flight over land normally.
On top of the initial sound, the boom continues while the object in question is travelling at supersonic speeds. But this will not be constantly heard by the human ear – it only affects observers positioned at a point that intersects a region in the shape of a geometrical cone behind the object.
As the object moves, this conical region also moves behind it and when the cone passes over the observer, they will briefly experience the boom.
