Supersonic Flight Venus Aerospace Stargazer, will cruise at Mach 4.  © Venus Aerospace

More than 20 years after the last Concorde flight, supersonic flights are coming back to the US.

President Donald Trump signed an order last week to lift the ban on supersonic flights over land in the US.The Concorde stopped flying in 2003, shortly after a deadly crash near Paris killed all 109 people on board.

Supersonic planes make a loud noise called a sonic boom, which can reach 110 decibels on the ground.

Supersonic FlightBoom Supersonic Overture passenger airliner.  ©  Boom Supersonic

Now, some companies are developing new supersonic planes designed to fly quietly without the sonic boom.