If you’re wondering if airplanes have brakes, the answer is yes.
Airplanes have brakes to help pilots slow down and land planes, in addition to helping pilots keep planes stationary on the ground.
There are different types of airplane brakes, most of which involve a disc and rotor system.
In such a system, the rotors use hydraulic pressure to force the discs to generate enough friction to convert the plane’s kinetic energy into heat energy.
Types and Construction of Airplane Brakes
There are different types of aircraft brakes.
Aircraft brakes are differentiated by their construction and mechanisms, but they all serve the same purpose.
Single Disc Brake
Single Disc brakes are the most common type of aircraft brakes.
Single disc brakes have a simple but effective mechanism, which consist of a single disc that rotates with the aircraft’s landing gear wheel and a brake caliper.
The caliper contains brake pads and pistons, which operate under hydraulic pressure applied by the pilot using a toe brake. The caliper actuates onto the disc to initiate braking.
Small aircraft sometimes use a modified version of the single disc brake. They will use a single disc placed between two pads attached to landing gear legs.
Dual Disc and Multiple Disc Brakes
The largest aircraft use dual and multiple disc brakes.
As single disc brakes are usually insufficient to provide enough braking force, dual and multiple disc brakes use multiple stationary discs placed between bronze or copper rotors.
The rotors and discs rotate with landing gear wheels.
Hydraulic pressure is applied to press the plates and create a large enough frictional force to halt the aircraft.
As multi-disc brakes require a large hydraulic force for initiating brakes, aircraft frequently use power brake or booster systems in conjunction with multiple disc brakes.
Segmented Disc Rotor Brakes
Segmented disc rotor brakes were developed from multi-disc brake systems and are most commonly used by large and heavy aircraft.
Segmented disc brakes are among the most powerful brakes, so they’re the standard for large planes.
A segmented brake system include components like pistons, pressure plates, and a backing plate
The segmented disc rotors contain spaces or open sections for releasing heat, hence the name.
They rely on the large hydraulic pressure produced from power brake systems to operate.
Segmented disc rotor brakes contain multiple sets of stationery, high friction brake linings that contact rotating segments of the wheel.
The rotors contain spaces or open sections for releasing heat, which is why they’re referred to as segmented disc rotor brakes.
Expander Tube Brakes
Expander tube brakes, which were developed between 1930 and 1950, are a low-pressure braking system, so they’re not as effective as modern single disc braking systems.
For this reason, expander tube brakes have mostly been phased out in favor of single or multi-disc brakes, but some planes still use them.
Expander tube brakes have a lightweight frame attached to the outer side of a rubber tube. Multiple brake blocks are attached to the frame, and both the frame and tube are placed inside a wheel drum.
The rubber tube is inflated when the plane begins braking.
This inflated tube pushes the brake pads to the inside of the wheel drum, which generates friction that slows the aircraft.
How Airplane Brakes Work
Virtually all aircraft brakes work by using friction.
They convert the plane’s kinetic energy to heat energy by generating friction between the plane’s brake’s rotating and stationary discs.
When the pilot presses on the plane’s brake pedal or activates the auto brake system, actuators in the brake move a piston.
This piston squeezes the rotating and stationary discs in the plane’s brakes, which generates friction that slows the wheel’s rotation.
The friction generated between the discs creates heat. As the plane’s kinetic energy converts to heat energy, the brakes absorb large amounts of heat, acting as a heat sink.
When braking, the aircraft’s disc’s temperature can exceed 1,800° C.
Airplanes Haven’t Always Had Brakes
In the early days of the aviation industry, airplanes did not have brakes.
Instead, pilots would reduce the aircraft’s speed as it skidded on the surface.
The friction generated from the aircraft skidding on the ground would reduce the plane’s speed and eventually stop it.
Brakes Are Located on An Airplanes’ Wheels
Most airplanes have brakes located on their wheels.
Typically, the brakes will be placed on the wheel’s inboard side.
Planes also use thrust reversers to slow down. Thrust reversers use the plane’s engine thrust to reduce speed.
When a Pilot Uses a Planes’s Brakes
Airplane brakes serve three purposes:
- Decelerate planes after landing
- To keep the plane stationary when needed
- Assist movement on the ground
During landing, pilots apply extra pressure on their brakes to achieve aerodynamic braking.
Pilots also use brakes when aircraft are parked in hangars to prevent them from rolling off–just like a car’s handbrake.
Brakes also assist planes during taxiing. As airplanes aren’t designed to be effective for traveling on the ground, brakes prevent sharp turns on the ground, which could damage planes.
How Airplanes Brake When Landing
Airplanes brake when landing using a combination of disc brakes, wing spoilers and reverse thrusters.
Airplane disc brakes during landing work similarly to automobile brakes. A pair of calipers squeeze pads against the plane’s landing gear rotors to generate friction for stopping the plane.
How Pilots Control The Brakes
Usually, pilots control airplane brakes using a mechanical or hydraulic system linked to brake pads in the cockpit.
Pushing the brake pad’s top right side activates the brakes on the right side of the plane.
Conversely, pushing the brake’s left side activates brakes on the plane’s left side.
Pilots step on either side depending on the direction they need to control the brakes.
In conclusion, yes, airplanes have brakes. Airplane brakes are not unlike automobile ones–both use friction to reduce speed and stop.
There are several types of aircraft brakes, with the most common being single disc or multiple disc brakes.