Airfield Surface Abrasion - Brake Performance Analysis
In the world of aviation, the friction effects of runway surfaces play a crucial role, particularly during critical phases such as landing and rejected take-offs. The Friction Assessment of Runway Surfaces (FARS) is a key concern for airports and airlines, and the Federal Aviation Administration (FAA) Runway Condition Assessment Matrix (RCAM) offers valuable insights into this matter.
Runway surface condition is a significant factor influencing braking effectiveness and friction. Wet or contaminated surfaces, such as those covered in water, slush, ice, or snow, drastically reduce braking effectiveness and friction, increasing landing distances and decreasing stopping performance. In contrast, dry runways offer better friction and braking.
Weather conditions also play a significant role. Precipitation, temperature, and wind can all affect braking. For instance, precipitation causes wet or contaminated surfaces, while temperature affects tire and brake performance. Headwind reduces landing speed and distance, while tailwind increases it.
The slope of the runway can also impact braking performance. An upslope runway helps reduce required landing distance by aiding deceleration, while a downslope runway has the opposite effect, increasing landing distance.
Contamination of the runway can also affect braking friction. Different contaminants have specific effects, so aircraft manufacturers provide landing distance adjustments in their manuals for various conditions, such as slush, ice, packed snow, and so on.
Tire and brake condition are also essential factors. Tire wear, brake type (carbon vs. steel), and heat all affect braking performance. Tire wear varies with outside temperature and runway abrasion, while carbon brakes offer durability and performance advantages but are expensive.
Aircraft braking systems, including aerodynamic braking, anti-skid systems, autobrakes, and thrust reversers, also influence effective braking and friction utilization.
Regarding how braking measurements are made in airport operations, runway condition reports (FICON/RCAM) provide regular measurements of runway surface friction. Specialized friction measurement vehicles assess braking coefficients and surface friction under various conditions (dry, wet, contaminated). These data feed into runway condition codes (RCAM) used by dispatchers and pilots.
Pilots and dispatchers also use aircraft manufacturer performance charts, adjusted for measured runway friction conditions, to plan landing distances and braking performance safely. Measurements of braking distances affect calculations of runway occupation time and capacity, important for managing traffic and minimizing runway occupancy time.
Standard operating procedures (SOPs) implemented by airlines and airports incorporate braking data, weather, and runway surface reports to optimize safety and predictability in landing operations.
In summary, runway braking performance depends on a complex interplay of surface condition, weather, aircraft systems, and operational factors. Regular friction measurements and runway condition reporting are crucial for accurate landing performance planning and safe airport operations.
The FAA RCAM provides a matrix for classifying runway conditions based on braking measurements, while the International Civil Aviation Organization (ICAO) offers a detailed classification for runway braking values. Tire marks are cleaned periodically by related professionals, usually during hours of low flight traffic or when the runway is notamed or closed for use. If a runway is notamed due to a cleaning process or other reasons, the operation may be continued using other runways if available at the airport.
Runway friction is the counterforce that occurs when an aircraft comes into contact with the runway surface and moves in one direction. Runway braking measurement values can be added to ATIS publications to enable pilots to be aware of up-to-date runway conditions.
- The science of runway surface management plays a significant role in the health-and-wellness of air travel, as it directly impacts the safety and efficiency of landing and take-off operations.
- In the industry of aviation, technology, particularly tools like the Friction Assessment of Runway Surfaces (FARS) and the Federal Aviation Administration (FAA) Runway Condition Assessment Matrix (RCAM), are vital for ensuring the fitness-and-exercise of aircraft during critical stages of flight.
- Financing for the maintenance and update of runway surfaces, as well as investments in aerospace technology for runway friction measurements, is a crucial aspect of ensuring the continued growth and safety of the global aviation industry.
