Transonic facts for kids

The Bell X-1, a special plane built to fly at transonic speeds.

Transonic flight is when an aircraft moves at speeds close to the speed of sound. This means it's going from slower-than-sound (subsonic) to faster-than-sound (supersonic). The speed of sound is about 1,236 kilometers per hour (768 miles per hour) at sea level.

When an airplane flies at transonic speeds, it's like it's pushing through an invisible wall. This "wall" is called the sound barrier. It happens because the air around the plane starts to behave differently.

What Are Flight Speeds?

Scientists and engineers divide flight speeds into different groups. This helps them understand how planes behave in the air.

• Subsonic: Slower than the speed of sound.
• Transonic: Around the speed of sound.
• Supersonic: Faster than the speed of sound.
• Hypersonic: Much faster than the speed of sound.

Understanding Transonic Speeds

Transonic flight happens when an aircraft is moving between Mach 0.8 and Mach 1.2. Mach 1 is exactly the speed of sound. So, a plane flying at Mach 0.9 is transonic, and one at Mach 1.1 is also transonic.

When a plane reaches these speeds, the air in front of it can't get out of the way fast enough. This creates special air waves called "shock waves." These shock waves cause a lot of drag, which is a force that tries to slow the plane down. It becomes very hard for the plane to go even faster. This is why breaking the sound barrier was a big challenge for early aircraft designers!

Breaking the Sound Barrier

For a long time, engineers thought it was impossible to fly faster than sound. They called this the "sound barrier." Many planes would shake violently or even break apart when they got close to Mach 1.

However, on October 14, 1947, Chuck Yeager became the first person to officially break the sound barrier. He did it in a special rocket-powered plane called the Bell X-1. This plane was designed with very thin wings and a shape that helped it push through the shock waves more easily. This historic flight opened the door for faster air travel and new aircraft designs.

Images for kids

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  Aerodynamic condensation around a transonic F/A-18 as it breaks the sound barrier.

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  Shock waves can sometimes be seen as faint disturbances above the wings of airliners.

See also

In Spanish: Velocidad transónica para niños