Mach Numbers y el/la Sound Barrier

Understanding Supersonic Velocidad

Learn Acerca de Mach

When un/una aircraft reaches Mach 1, eso's traveling at el/la speed of sound. Go faster, y tu're supersonic. But que exactamente es un/una Mach numero, por que does el/la speed of sound change, y que happens cuando tu break el/la sound barrier? This guia explains el/la physics behind algunos of el/la fastest speeds humans achieve.

What Is un/una Mach Number?

Mach numero es el/la ratio of un/una object's speed un/una el/la local speed of sound:

Mach = Object speed ÷ Velocidad of sound

  • Mach 0.5: Half el/la speed of sound (subsonic)
  • Mach 1.0: El/La speed of sound (sonic)
  • Mach 2.0: Twice el/la speed of sound (supersonic)

Named after Austrian physicist Ernst Mach (1838-1916), quien studied shock waves.

Why el/la Velocidad of Sound Varies

El/La speed of sound depends on air temperature (y thus altitude):

AltitudeTemperaturaVelocidad of Sound
Sea level15°C (59°F)761 mph (1,225 km/h)
10,000 ft-5°C (23°F)722 mph (1,162 km/h)
20,000 ft-25°C (-13°F)685 mph (1,102 km/h)
35,000 ft-54°C (-65°F)660 mph (1,062 km/h)
40,000 ft-57°C (-70°F)659 mph (1,061 km/h)

Sound travels faster in warmer air porque air molecules move mas energetically.

Velocidad Regimes

RegimeMach RangeCharacteristics
SubsonicBelow Mach 0.8Normal airflow, la mayoria aircraft
TransonicMach 0.8-1.2Mixed sub/supersonic flow, instability
SupersonicMach 1.2-5.0Shock waves, sonic booms
HypersonicMach 5.0-10.0Extreme heating, especializado vehicles
High hypersonicAbove Mach 10Re-entry vehicles, theoretical aircraft

Mach Conversion at Different Altitudes

At Sea Level (15°C)

MachMPHKM/H
0.5380612
0.856471,041
1.07611,225
2.01,5222,450
3.02,2833,675

At Cruise Altitude (35,000 ft, -54°C)

MachMPHKM/H
0.5330531
0.85561903
1.06601,062
2.01,3202,124
3.01,9803,186

El/La primero supersonic flight fue made by Chuck Yeager in el/la Bell X-1 on October 14, 1947, reaching Mach 1.06 at 43,000 pies.

Aviation History, Breaking the sound barrier

Famous Aircraft Speeds

AircraftMax MachMPHKM/H
Boeing 7470.92~614~988
Concorde2.04~1,350~2,173
F-22 Raptor2.25~1,500~2,414
SR-71 Blackbird3.32~2,193~3,529
X-15 (record)6.70~4,520~7,274
Space Shuttle (re-entry)~25~17,500~28,000

Why Mach Numbers Matter

Aircraft Design

Aerodynamics change dramatically at diferente Mach regimes. Aircraft designed for subsonic flight won't trabajar supersonically, y vice versa.

Pilot Communication

Pilots usar Mach numeros at high altitudes porque true airspeed becomes misleading as air density changes. "Mach 0.85" means el/la mismo thing regardless of altitude.

Structural Limits

Aircraft have maximum operating Mach numeros (Mmo) beyond cual structural damage o control problems occur.

Conclusion

Mach numeros proporcionar un/una universal manera un/una describe speed relative un/una sound—esencial in aviation y aerospace. Mach 1 es el/la speed of sound, cual varies with temperature (aproximadamente 660-760 mph depending on altitude). Understanding Mach numeros helps interpret aircraft performance datos y appreciate el/la remarkable achievement of supersonic y hypersonic flight.

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Mach Numbers y el/la Sound Barrier | YounitConverter