Exceeding the speed of sound

Exceeding the speed of sound
The pioneer era of aviation began in 1903
when the Wright brothers' airplane made its first successful flight.
Conquering the air promoted a rapid technical development in aviation.
As a result, aircraft began to fly faster and reach higher altitudes.
With the increase in speed, it was only a matter of time
before airplanes could reach the speed of sound.
But what exactly is the speed of sound?
The speed of sound is the velocity of sound waves
in a certain medium which is air in this case.
Sound waves propagate in all directions at the same velocity
which, however, depends on the temperature,
humidity
and air pressure as well.
The velocity of sound waves at sea level in dry air at 15 °C is 1,225 km/h.
What happens when an object, in this case the aircraft,
reaches the speed of the sound it has emitted itself?
The aircraft catches up with the sound waves it emits
which become compressed in front of it,
and their oscillations are added together.
The resulting vibration once literally shook
poorly built aircraft apart and pilots felt as if they had hit a wall.
An airplane that breaks through the sound barrier
is surrounded by cone-shaped wave fronts
that formed out of these amplified sound waves.
An observer, over whom these wave fronts pass,
can hear a sonic boom.
Aboard the aircraft, however, this sonic boom cannot be heard,
since it is flying at supersonic speeds,
that is it is moving faster than the speed of sound.
The younger Wright brother, Orville, was still alive
when Chuck Yeager, an American test pilot, exceeded the speed of sound
with an experimental rocket-powered aircraft in 1947.
This event opened another chapter in the history of aviation.