Sound Barrier . The term came into use during World War II , when a number of aircraft began to have compressibility problems (as well as other unrelated problems) when flying at high speeds, and it fell into disuse in the 1950s , when aircraft they started breaking that barrier on a routine basis.
[ hide ]
- 1 In aerodynamics
- 2 History
- 3 Today’s supersonic aircraft
- 4 External link
- 5 Sources
A term that refers to the compressibility effects experienced by supersonic aircraft when their speed with respect to air approaches the local speed of sound (1,223 km / h at sea level under normal conditions. When an airplane approaches the speed of Sound, the way air flows around its surface changes and becomes a compressible fluid, resulting in increased resistance.
In the 1930s they failed to produce an aircraft capable of entering the compressibility region. In addition, in the years that followed, aviation industries around the world shifted from developing new models to mass-manufacturing minimally modified versions of their existing designs, as the proximity of the war caused governments to demand higher levels of production.
The main obstacle that aerodynamic experts faced – which would not be resolved until the late 1940s – was the inability to construct an aerodynamic tunnel capable of providing accurate results for speeds in or near the compressibility zone. same. In the absence of such data, high-speed airplane designers simply continued to produce increasingly refined versions of traditional designs, endowed with increasingly powerful versions of traditional engines.
In 1944 the first generation of jet planes came to join propeller fighters . Aside from flying at somewhat higher speeds, the new jets employed traditional aerodynamic designs, with the classic wing profile with much more curved upper surfaces than the lower ones.
In order to prevent a vacuum from forming, the air passing over the wings must advance faster than the air flowing below. Therefore, the air above the wings was the first to encounter localized compressibility phenomena that, in turn, affected the controllability of the aircraft.
Surprisingly, it appears that none of the warring nations of World War II conducted consistent research on compressibility, other than exploring model-by-model high-speed chopping ability, after which pilots were instructed not to exceed certain speeds. at a given altitude.
Charles Elwood Yeager was the first man to officially cross the barrier of sound, the 14 of October of 1947 , flying the experimental Bell X-1 aircraft speed Mach 1 at an altitude of 45,000 feet.
However, Hans Guido Mutke claimed to have crossed the sound barrier before Yeager, on April 9, 1945, in a Messerschmitt Me 262, although there is no scientific evidence of this achievement.
Today’s supersonic aircraft
Today’s supersonic aircraft are built with advanced materials capable of withstanding the heat caused by air friction at such high speeds. Most are military aircraft , with the famous exception of the Franco-British luxury commercial aircraft Concorde, also known as supersonic transport (SST), which made its first test flights in 1971 and began transporting passengers to the United States in 1976 .
Capable of achieving speeds around Mach 2, the Concorde made the round trip across the North Atlantic in less time than a normal reactor needs to make the outward flight. Only 16 out of the 400 units originally planned were built as the noise produced by this slim, attractively designed aircraft always created environmental problems.
In April of 2003 the end of commercial flights of the Concorde due to weak demand and rising maintenance costs, and in October the same year he made his last flight was announced.