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This blog is a compilation of publicly available information on ’s (Paris, France) production of carbon fiber-reinforced carbon (carbon/carbon) brake discs for aircraft. The company published a video earlier this year (see below) that walks through its production steps. Carbon/carbon (C/C) brake discs are still one of the highest volume applications for ceramic matrix composites (CMC), but that is changing as demand increases for industrial and aerospace end uses. Having toured Brembo’s facility near Bergamo, Italy, which produces C/C brakes for racing cars (there is also a sidebar on their CMC brake disc production for street cars), I thought it would be interesting to look at Safran’s production sites, output and innovations in processing and ongoing initiatives for increased sustainability.

With more than 40 years of experience — having introduced carbon fiber-reinforced C/C brakes on Airbus A310 aircraft in 1985 — (Vélizy-Villacoublay, France) claims the title of world leader in C/C brakes for aircraft with more than 100 seats. It reportedly equips 55% of these commercial airliners worldwide and supports 500+ airlines and 1500+ military programs. The company produces carbon brakes at three facilities: Villeurbanne, France (in Lyon); Walton, Kentucky in the U.S. (south of Cincinnati, Ohio) and in Sendayan, Malaysia. It is also building a fourth facility roughly 30 minutes east of Lyon, set to open by 2030.

Carbon brakes are lighter, more efficient and two to three times more durable than steel brakes, helping operators reduce fuel consumption, cost and CO₂ emissions. Safran reports that the quantity of CO₂ prevented during flight thanks to C/C brakes is 10 times more than what is generated during the brake manufacture, totaling several hundred tons of emissions avoided fleet-wide every year.

Production worldwide

At its historic Messier-Bugatti-Dowty site in Villeurbanne, Safran reported a 2023 production of 5,000 wheels and 6,000 brakes per year.

The Walton, Kentucky site opened in 1999 and reportedly produces close to 140,000 carbon brake disks and more than 9,500 wheels and brake sets per year. Its 350 employees support Boeing 737, 777 and 787 aircraft, the Airbus A320 family, and C-17 and KC-135 military aircraft. The company announced an expansion in 2023 to include 92 new jobs, new equipment and automation to boost production.

Celebrating its 10^th anniversary in January 2025, the Sendayan, Malaysia site produces 350 metric tonnes of C/C per year, including roughly 80,000 new carbon brake disks. Each year, it also refurbishes more than 15,000 heat sinks — or heat packs, comprising a stack of brake discs —and overall supports 100-150 airlines in the region.

Carbon aircraft brake configuration

Each wheel in an aircraft’s landing gear is equipped with a brake. A common configuration for carbon brakes uses four rotational discs (rotors) and three or four stationary discs (stators) alternating in a heat stack or heat pack. The rotors engage with the wheel’s drive keys and thus rotate with the wheel. The stators include an end plate facing outward and a pressure plate at the other end of the stack (see images below).

During braking, fluid from the brake piston moves the pressure plate to compress the rotors and stators against the end plate. The resulting friction converts kinetic energy into heat, decelerating the wheel. During landing, the C/C rotors and stators can see 700°C, but C/C brake discs can easily withstand 1000°C and higher. This heat resistance is what enables carbon brakes to maintain structural integrity without failure or degradation (e.g., brake fade).

SepCarb IV for Long Life brakes

In April 2018, Safran worked with Airbus to install new Long Life carbon brakes on A320neo aircraft. That product, the SepCarb IV brake, was the first C/C brake put into service since the release of the Sepcarb III 15 years prior. This new “Long Life” brake features two major innovations: SepCarb IV carbon and Anoxy 360, a new system to protect brake disks from oxidation. These not only provided improvements during use but also during manufacturing to address the challenge at that time of meeting the ramp in A320neo production rates.

Safran’s C/C brake production site in Villeurbanne, on the outskirts of Lyon, France, developed a unique manufacturing method for producing SepCarb IV on an increased industrial scale. Instead of performing impregnation of carbon fiber preforms with solvent and then damping or drying these as two separate steps, it combined them in the same equipment — eliminating handling in between and reducing both production time and cost.

SepCarb IV also used ceramic particles to improve wear of the C/C brake, enabling a 30% reduction in brake usage. This provided benefits not only for aircraft operators, but also further helped to meet the A320neo production rate. Safran also modified the process to reduce the amount of nitrogen it consumed during thermal processing and eliminated atmospheric emissions, collecting the process waste as a liquid instead.

A second impregnator was added in 2019, and the process was rolled out to other sites.

As described in its , the manufacturing process Safran uses for its C/C brake discs involves four main steps:

• Production of carbon fiber preforms, which involves needling layers of continuous fiber.
• High-temperature carbonization of preforms and densification of the carbon matrix via chemical vapor infiltration (CVI).
• Machining the discs and performing quality assurance including dimensional checks.
• Final processing including spraying and heat treatment of an oxidation protection coating, followed by assembly of multiple discs into a single C/C brake unit.

New production site in Lyon, environmental goals

Safran is building a new carbon brake plant at the Plaine de l’Ain Industrial Park (PIPA) near Lyon. Scheduled to open in 2030, Safran’s latest C/C brake production site will provide a 25% increase in the company’s overall production volume by 2037. The 30,000-square-meter facility will be highly automated, with ≈100 employees when it opens and double that at full capacity.

The company is targeting Lyon to be a zero-emissions facility (Scope 1 and 2). Because energy can account for up to 30% of the cost of manufacturing a carbon brake, Safran chose the Lyon site for the availability of low-carbon electricity. It will also use biomethane as its carbon matrix precursor injected during CVI. As a result, the site’s electricity and gas consumption will be reduced by nearly 30% and water consumption by 80%. In addition, the heat generated by the C/C production process will be recovered to supply a heating network. Some of these technologies will also be rolled out at other Safran C/C brake facilities.

Safran overall has committed to reduce the carbon emissions of its activities by 2030 to ≈50% compared to 2018. In its , the company reported achieving a 35% reduction in direct emissions across all its businesses in 2025 versus 2018.

For Safran Landing Systems, the Sendayan, Malaysia site has reduced its CO₂ emissions by 27% since 2018, including reuse of effluent gases released during carbon disc production to generate 20% of the site’s electricity and widespread use of variable frequency drives, which tailors the speed (and power use) of electric motors of machines to their actual needs. The site is also planning to implement a new power management system to control and optimize site utility consumption including electricity, gas and water. According to a July 2024 newsletter, the Sendayan site signed a 21-year agreement with a local solar power producer which will start in 2026 and add another 10% of renewable energy to the current electricity mix. This complements a partnership signed in 2023 with a local firm generating electricity from biomass, which covers 30% of the site’s needs.

Extending C/C disc service life, reusing waste

Another key initiative that embraces emissions reductions via circularity is a carbon brake disk refurbishment process that was developed by Safran Landing Systems more than 30 years ago. Today, around 30% of the discs it delivers to airlines are refurbished using this method.

Although the average lifespan of Safran carbon brake discs varies by aircraft model and operational factors, it is not uncommon for them to see 2,000 to 2,500 landings between overhauls. Subjected to temperatures exceeding 1,000°C on a daily basis, they do eventually wear — although lasting much longer than steel discs — and are decommissioned at a set limit before they are fully worn out.

“By refurbishing two worn discs, we obtain two half-discs that are then reused to create a new disc,” explains Jean-Luc Noirjean, product strategy manager at Safran Landing Systems. “This refurbished disc performs just as well as a newly manufactured one. Airlines provide us with heat sinks that have reached their regulatory limit. In return, we send them a refurbished brake disc; this is what we call a standard exchange.”

The 30% of discs delivered that are refurbished means 30% less CO₂ emissions, notes Jean-Baptiste Lassalle, head of Safran Landing Systems’ Wheels and Brakes Division. “We set up this process in the mid-90s for the Airbus A300, A310 and A320 programs to reduce manufacturing costs … but it also sparked a virtuous circular economy dynamic within our operations.”

Going forward, Safran Landing Systems will investigate new ways to recycle even these refurbished aircraft brake discs at the end of their life for use in other industries. At the same time, it has implemented several waste reduction projects. “We’ve developed a process to manufacture felt from fibers that are not used during production, which represents nearly half of our fiber purchases,” says Lassalle. “This felt, which is produced by a partner company, serves as insulation for our furnaces. We’ve also set up a system to recycle machining dust from our carbon discs [for use] in cement production plants. More broadly, the projects that we are setting up aim to minimize material waste throughout our entire production cycles.”

These environmental initiatives and circular economy ramp-up have led to an organization that is increasingly methodical and structured, says Lassalle. “Last year, we created a dedicated position to consolidate evaluation methods for our product life cycles and carbon emissions. This position also focuses on enhancing the recyclability of our products. The more we develop these types of initiatives, the more we pave the way for new economic models that fully integrate circular economy principles.”

Digital transformation, future growth

Safran is also implementing a variety of digital transformation initiatives including robotic process automation (RPA) using software to automate repetitive and mundane tasks as well as cobots, augmented reality and automated machines to speed production. The company is also implementing health monitoring and predictive maintenance into its products, including brakes, and is developing ways to leverage AI. For example, Safran Landing Systems worked with its partner in machine programming, MHAC Technologies (Écully, France), to standardize and automate 3D measurement and machining of its carbon brake discs. Using machine learning, the team reduced the number of programs run for different brake discs from more than 100 down to several dozen and further accelerated production.

This continued increase in output will be needed, because the demand for carbon brakes continues to increase as aircraft fleets are modernized both for higher performance and reduced fuel consumption and emissions. This growth can be seen in the forecast shown here from the Global CMC Market Report published in 2023 by the network. Denny Schüppel, managing director for the Ceramic Composites network, notes that Safran Landing Systems is just one of several manufacturers of C/C brakes for aircraft and that non-aircraft brake applications for C/C materials are also growing quickly.

The 2023 CMC market report also includes a table showing the number of heat packs per aircraft type and notes that, depending on the number of landings per day, most aircraft receive new heat packs every 4-18 months with roughly 50% of all C/C aircraft brakes experiencing a second life. Schüppel says an update of the Global CMC Market Report is scheduled to be published in March 2026.

Schüppel is also a co-author on a that gives further details on C/C heat stacks, their production and refurbishment as it explores a life cycle assessment (LCA) versus the significant weight and fuel savings they achieve. The report finds that “even the least favorable C/C use case scenario combination relates to fewer CO₂ equivalents than the most favorable metallic use case scenario.”