What Is a Supercritical Airfoil and Why Do Modern Jets Use It?

Look at the wing of a modern airliner like the Boeing 787 or Airbus A350, and you will notice something unusual — the top of the wing looks flatter, and the back edge curves sharply downward. This is not a styling choice. It is the result of one of the most important aerodynamic inventions in aviation history: the Supercritical Airfoil.

This wing design allows jets to fly faster, farther, and with less fuel.

What Is a Supercritical Airfoil?

A supercritical airfoil is a special wing shape designed to:

  • Delay shockwave formation
  • Reduce drag at near-supersonic speeds
  • Improve fuel efficiency

It was developed specifically for aircraft flying close to the speed of sound, where traditional wings become inefficient.

The Problem with Old Wing Designs

Traditional airfoils have:

  • A curved top surface
  • A pointed leading edge

At high speeds (Mach 0.75–0.85), air flowing over the wing can locally exceed the speed of sound, creating shock waves.

What Is a Supercritical Airfoil and Why Do Modern Jets Use It?
What Is a Supercritical Airfoil and Why Do Modern Jets Use It?

These shock waves cause:

  • Huge drag increase (wave drag)
  • Loss of lift
  • Buffeting and instability
  • High fuel burn

This phenomenon is called the drag divergence problem.

How a Supercritical Airfoil Solves It

A supercritical airfoil changes the wing shape to control airflow:

Key design features:

  • Flatter upper surface
  • Thicker mid-section
  • Curved downward trailing edge
  • Blunt leading edge

These features:

  • Keep airflow slower over the wing
  • Push shockwaves further back
  • Reduce shock strength
  • Lower drag dramatically

The aircraft can now cruise faster with the same fuel.

Why It Is Called “Supercritical”

It allows the aircraft to fly efficiently beyond the critical Mach number
The speed where shockwaves normally begin to appear.

In simple words:
It lets jets fly closer to the speed of sound without penalties.

Where Are Supercritical Airfoils Used?

Almost all modern jet aircraft use them:

  • Boeing 737, 777, 787
  • Airbus A320, A350, A380
  • Military jets and business jets

Without supercritical airfoils, today’s long-range fuel-efficient flights would not exist.

Fuel Savings & Performance

Because drag is lower:

  • Less thrust is needed
  • Engines burn less fuel
  • Aircraft can fly farther
  • Airlines save millions of dollars

This is one of the main reasons modern jets are far more efficient than older aircraft.

Conclusion

The supercritical airfoil is a silent revolution in aviation.
Passengers never see it, but every modern jet depends on it.

By reshaping airflow near the speed of sound, it made today’s high-speed, long-range, fuel-efficient air travel possible.

Without it, modern aviation simply could not exist.

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