The speed of sound
Not so long ago people didn’t believe that a person will ever be able to flight.
But the progress isn’t sleeping, it is always moving on, and today thanks to different technologies we can flight at almost any height and with different speeds. One of the biggest achievements was reaching the sound barrier, in order to do this the plane must have the speed of 1235 km/h. This means that the aircraft will move so fast that you will hear his movement after he will pass your view. Here you can see some photos where is captured the moment when the aircraft passes the speed of sound. Enjoy!