Air Brakes: How Airplanes Slow Down When Flying


Airplane flying

Ever wonder how airplanes slow down when flying? Faster isn’t always better. If an airplane is approaching a runway, it may need to slow down. While different types of airplanes feature different braking systems, many of them use air brakes. Pilots can engage the airplane’s air brakes to create drag and, thus, slow down.

Overview of Air Brakes

Air brakes are flight control surfaces that are designed to slow down airplanes during flight. They increase drag when engaged.

Drag, of course, is the aerodynamic force that opposes airplanes during flight. All airplanes will be exposed to drag during flight. They must overcome this aerodynamic force to achieve and maintain lift. Otherwise, airplanes would essentially fall out of the sky. Air brakes are control surfaces that increase drag so that airplanes slow down during flight.

Air brakes have been around for nearly a century. Some of the earliest known air brakes consisted of wing flags. Pilots could engage them via a lever. Pulling the appropriate lever in the cockpit would deploy the air brakes. Air brakes have since gone through numerous changes, but their underlying concept remains the same: they are flight control surfaces that increase drag when engaged.

How Air Brakes Work

Air brakes work by expanding so that the airplane is exposed to greater drag. They are spoiler-like flight control surfaces. Like traditional spoilers, air brakes are found on the wing. Most airplanes have at least one air brake per wing.

When engaged, air brakes will expand vertically. This expansion will reduce the aerodynamic properties of the airplane’s wings. As the air brakes expand, they consume space above and/or below the wings. The wings will essentially become less aerodynamic, and the airplane will be exposed to greater drag.

Air brakes will still affect lift, but they are designed to slow down airplanes while minimizing their impact on lift. They increase drag, which causes airplanes to slow down while maintaining a sufficient amount of lift.

Air Brakes vs Landing Gear Brakes

In addition to air brakes, many airplanes feature landing gear brakes. Landing gear brakes are part of an airplane’s landing gear.

Landing gear brakes are similar to automotive brakes. Most landing gear systems consist of wheels. Landing gear brakes will press against these wheels so that the airplane slows down. Landing gear brakes, though, are designed for use when airplanes are on the runway, whereas air brakes can be used when airplanes are either flying or on the runway.

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