<P> In dry air at 20 ° C ( 68 ° F ) , the speed of sound is 343 metres per second ( about 767 mph , 1234 km / h or 1,125 ft / s ) . The term came into use during World War II when pilots of high - speed fighter aircraft experienced the effects of compressibility , a number of adverse aerodynamic effects that deterred further acceleration , seemingly impeding flight at speeds close to the speed of sound . These difficulties represented a barrier to flying at faster speeds . In 1947 it was demonstrated that safe flight at the speed of sound was achievable in purpose - designed aircraft thereby breaking the barrier . By the 1950s new designs of fighter aircraft routinely reached the speed of sound , and faster . </P>
<P> In dry air at 20 ° C ( 68 ° F ) , the speed of sound is 343 metres per second ( about 767 mph , 1234 km / h or 1,125 ft / s ) . The term came into use during World War II when pilots of high - speed fighter aircraft experienced the effects of compressibility , a number of adverse aerodynamic effects that deterred further acceleration , seemingly impeding flight at speeds close to the speed of sound . These difficulties represented a barrier to flying at faster speeds . In 1947 it was demonstrated that safe flight at the speed of sound was achievable in purpose - designed aircraft thereby breaking the barrier . By the 1950s new designs of fighter aircraft routinely reached the speed of sound , and faster . </P>
how fast to go to break the sound barrier
how fast to go to break the sound barrier
In dry air at 20 ° C ( 68 ° F ) , the speed of sound is 343 metres per second
In dry air at 20 ° C ( 68 ° F ) , the speed of sound is 343 metres per second