How Often Do Aircraft Need Their Brakes Changed?

Aircraft braking systems are crucial to safe landings, and they regularly undergo intense inspection and servicing to guarantee their reliability. Typically, aircraft brakes can last between 1000-2000 landings before requiring replacement, and their longevity depends on the particular material they are made from, which is often steel or carbon. In particular, steel brakes remain durable for about 1000 landings, while more expensive carbon brakes can endure about 2000 landings. However, to reinforce safety and durability, most modern airplanes feature carbon brakes as they are lighter, more durable, and require lower maintenance costs. Moreover, carbon brakes can resist higher temperatures, which makes them a more economical choice than steel brakes.

There are a number of factors that determine what makes a suitable aircraft brake system and how often they need to be changed. In addition to durability, optimal braking systems must have the ability to hold the aircraft at full static run up and provide adequate control while taxiing on the ground. More than that, brakes should also be able to smoothly stop the vehicle within the length of the runway and keep it from moving when parked. Once the brakes are unable to perform one or more of these tasks, they are ready to be repaired or replaced. Read on to learn more about how aircraft brakes are designed to perform these impressive functions.

Several things that manufacturers have taken into consideration when designing aircraft brakes are the number of discs required to adequately support the vehicle based on its size and weight, the discs’ diameter, and the material it's made from. The most common brake disc material was steel until 1963, when it was replaced by beryllium because of its improved thermal properties. Though, this only lasted until around the 1980’s when the discovery of beryllium oxide toxicity caused the switch to carbon brakes for commercial airplanes.

Another reason that carbon replaced beryllium is due to the fact that it has a higher specific heat tolerance. Steel and beryllium both have a lower specific heat than carbon, meaning that they tend to lose strength at higher temperatures, reducing overall brake weight. On the other hand, carbon has higher thermal conductivity which allows quicker heat transfer and more uniform heat distribution throughout the disc. With lower thermal expansion, higher thermal shock resistance, and a higher temperature limit than steel, carbon is your best choice in aircraft brakes.

In order to brake properly, the brake cylinder must deliver the right pressure and fluid volume to the caliper. The brake system absorbs heat energy developed during braking, and as the disc increases in size, so too does the amount of heat energy it can absorb. Since these parts operate under extreme stress and friction, they are vulnerable to malfunction and damage, such as overheating, squealing, and dragging. Overheating happens when the frictional heat involved in braking becomes excessive, which can weaken the brake parts to the point of failure. An inspection for brake overheating involves checking the brake housing for cracks and/or buckling, as any amount of brittleness caused by overheating can cause the brake to fail under high pressure.

Next, squealing occurs when brake linings are not properly aligned along the disc. Disc overheating may damage the surface layer of the disk, causing uneven surfaces that chatter or squeal. To solve this problem, an inspector must check on the brake and landing gear system to avoid further damage. On the other hand, brake dragging happens when the return mechanism malfunctions when the brakes are not currently in application. This drag wears the lining, leading to the damage of the disc. Dragging happens as a result of the expansion of air in the brake fluid line by heat, and it is recommended to bleed the brakes to remove air in the system to get rid of drag in this case. If dragging occurs as a result of the return pin slipping into the auto adjuster pin grip, the units should all be returned to the appropriate positions.

Those on the search for high-caliber aircraft brake systems and more are encouraged to choose Aviation Orbit as their procurement partner. With more than 2 billion new, used, obsolete, and hard-to-find components available for immediate purchase in our inventory, you will find what you need in rapid time. Once you have discovered items of interest, fill out the RFQ form found across our website to request a competitive quote for your comparisons. With the information you provide in your submission, a skilled team member will respond with a customized solution in minutes.