Runways are the backbone of aviation, ensuring that planes can take off and land safely. Over time, though, the repeated friction from aircraft tires during landings leaves a significant amount of rubber residue on the runway surface. This buildup can create serious safety hazards, reducing the runway’s friction and potentially leading to accidents, especially in wet conditions.

So, how do airports tackle this issue? Rubber removal from runways is a critical part of maintaining runway safety and ensuring smooth operations. In this article, we’ll explore the methods used to remove rubber from runways, why it’s so important, and how it keeps aviation infrastructure running efficiently.

Why Rubber Accumulates on Runways

When an aircraft touches down, its tires go from zero to high-speed rotation almost instantly. This creates tremendous friction between the tires and the runway surface. While modern aircraft tires are designed to withstand these forces, small amounts of rubber are worn away and left on the runway during each landing. Over time, this rubber residue builds up, especially on the touchdown zones, forming a layer that can reduce friction.

The friction between the aircraft’s tires and the runway is essential for safe landings, particularly in preventing skidding and enabling aircraft to stop within a safe distance. When too much rubber accumulates, it reduces the runway’s grip, which can be especially dangerous during wet or icy conditions. For this reason, airports must regularly remove rubber buildup to ensure the runway surface remains safe.

How Rubber Buildup Affects Safety

Runway rubber buildup, if not managed, poses several safety risks:

Reduced braking efficiency: Excess rubber reduces the coefficient of friction between the aircraft’s tires and the runway. This can make it harder for pilots to bring the plane to a stop, especially in wet conditions.
Skid resistance: A slippery runway increases the risk of aircraft skidding during landing or while taxiing.
Aquaplaning (hydroplaning): Rubber buildup can contribute to aquaplaning, where a layer of water forms between the tires and the runway during rain, reducing tire contact with the surface and making it difficult for the aircraft to slow down.

To ensure safety, airports must routinely measure the runway’s friction levels and remove excess rubber buildup when needed. But how exactly is this done?

Methods of Rubber Removal From Runways

Airports use specialized equipment and techniques to remove rubber buildup from runways efficiently and safely. The most common methods include high-pressure water blasting, chemical solvents, and mechanical scrubbing.

1. High-Pressure Water Blasting (Hydroblasting)

One of the most widely used methods for removing rubber is high-pressure water blasting, also known as hydroblasting. This method involves using water at extremely high pressures—typically between 15,000 and 40,000 psi—to strip the rubber from the runway surface.

Hydroblasting is effective because it targets the rubber without damaging the underlying runway pavement. The high-pressure water breaks down the rubber residue and lifts it off the surface, leaving the runway clean and ready for use. Additionally, this method does not rely on chemicals, making it an eco-friendly option for airports focused on sustainability.

2. Chemical Removal

Another method of rubber removal is using chemical solvents. Specially formulated chemicals are applied to the rubber-coated sections of the runway, which dissolve the rubber over time. Once the chemicals have broken down the rubber, the residue is washed away with water.

While effective, this method is less common today due to environmental concerns. Chemicals used in the process may pose a risk to nearby ecosystems if not managed carefully, and they require more time and effort to ensure proper disposal. Nevertheless, some airports still use chemical removal in specific cases where hydroblasting may not be sufficient.

3. Mechanical Scrubbing

Mechanical scrubbing is another option for removing rubber from runways. This method involves using machines equipped with abrasive brushes or rotating blades that physically scrape away the rubber. The equipment passes over the runway, dislodging the rubber from the pavement surface.

This method is often used as a follow-up to hydroblasting or chemical removal to ensure any remaining rubber is completely removed. While effective, mechanical scrubbing can be more abrasive on the runway surface, and it requires more time than hydroblasting.

Regular Maintenance: How Airports Keep Runways Safe

Airports must follow strict guidelines for runway maintenance to ensure safe operations. Regular friction testing is essential to measure the runway’s grip and determine when rubber removal is needed. Many airports use friction testing vehicles equipped with sensors that measure the skid resistance of the runway in various conditions.

Once friction levels fall below safety standards, the airport schedules rubber removal operations. Depending on the climate, traffic, and frequency of landings, some airports may perform rubber removal several times a year, while others may do it on a more seasonal basis.

How Often Is Rubber Removal Required?

The frequency of rubber removal depends on several factors, including:

Runway usage: Airports with high traffic, especially those handling large, heavy aircraft, tend to accumulate rubber more quickly.
Climate: Runways in regions with frequent rain or snow may require more regular rubber removal to prevent aquaplaning and maintain friction in wet conditions.
Type of runway surface: The material used to construct the runway also affects how quickly rubber builds up. Some surfaces, like porous asphalt, may allow water to drain more effectively, reducing the rate at which rubber buildup impacts friction.

On average, major airports with high volumes of air traffic typically perform rubber removal operations every three to six months, while smaller airports may need it only once or twice a year.

Safety Considerations During Rubber Removal

Rubber removal is a carefully planned operation to minimize disruptions and ensure safety. Here are some key considerations during the process:

Timing: Rubber removal is typically scheduled during off-peak hours to minimize disruption to flight schedules.
Safety for ground crews: The personnel performing rubber removal wear protective equipment to guard against the high-pressure water and chemicals used in the process.
Temporary closures: Sections of the runway may be temporarily closed during the operation to ensure both the safety of the crews and the efficiency of the procedure.

The Future of Rubber Removal: Sustainable Innovations

As environmental concerns grow, airports are increasingly looking for sustainable solutions for runway maintenance. While hydroblasting is already a more eco-friendly option compared to chemical removal, researchers are exploring ways to further reduce the environmental impact of runway cleaning.

Some airports are experimenting with biodegradable solvents that can break down rubber without harming nearby ecosystems. Others are investing in more energy-efficient hydroblasting equipment that uses less water and produces fewer emissions. These innovations aim to balance safety, efficiency, and environmental responsibility in the future of runway maintenance.

Conclusion

Rubber removal from runways is a crucial part of maintaining aviation safety, ensuring that aircraft have the friction needed for safe landings and takeoffs. By using methods like high-pressure water blasting, chemical solvents, and mechanical scrubbing, airports can effectively remove rubber buildup and keep runways in optimal condition.

Regular runway maintenance not only reduces the risk of skidding and aquaplaning but also extends the lifespan of runway surfaces. As airports continue to adopt sustainable practices, the future of runway maintenance will likely focus on balancing safety and environmental considerations, ensuring safe and smooth operations for years to come.