NOISE EDUCATION
Aircraft noise is influenced by many factors, including aircraft type, altitude, flight activity, weather, airspace, runway use, and time of day. This page provides background information to help residents understand how aircraft noise is experienced, how aviation activity around Centennial Airport is organized, and what programs and voluntary practices are used to address community noise concerns.
AIRSPACE & FLIGHT ACTIVITY
Aircraft operating around Centennial Airport are part of the National Airspace System, which includes controlled airspace, airports, navigation facilities, procedures, regulations, and air traffic control.
Different classes of airspace establish different operating requirements for pilots and aircraft. Centennial Airport operates within Class D airspace, while the surrounding Denver metropolitan area also includes Denver International Airport’s Class B airspace and other controlled areas.
Flight schools use practice areas throughout the Denver region for pilot training. Local examples include 3 Towers, Elizabeth, Fairgrounds/Kiowa, and Louviers.
Available operating altitude within each area varies based on terrain, surrounding airspace, and other aviation requirements.
Federal Aviation Regulation 91.119 establishes minimum safe-altitude requirements for aircraft. Requirements vary depending on the type of area being flown over and include exceptions associated with takeoff and landing.
UNDERSTANDING AIRCRAFT NOISE
Sound is created by vibrations traveling through air or other materials. Noise is generally understood as sound that is unwanted, disruptive, or unpleasant, and people may experience the same sound differently.
Aircraft also produce different types of sound. Jet aircraft generally create sound across a broader frequency range, while propeller aircraft produce stronger low-frequency sound. Those differences can affect how aircraft are heard and perceived from the ground.
Sound level is measured in decibels, or dB. The sound experienced on the ground can change based on distance from an aircraft, the number of aircraft operations occurring over time, and atmospheric conditions.
Increasing distance from a sound source reduces sound levels, while increasing the number of aircraft operations can increase the overall perception of noise.
Weather can also affect how sound travels. During a temperature inversion, warmer air above colder surface air can cause sound waves to refract differently, which may make aircraft noise more noticeable in some locations.
DAY-NIGHT SOUND LEVEL
Day-Night Sound Level, or DNL, is a metric used to describe cumulative environmental noise exposure over a 24-hour period.
The calculation applies additional weighting to nighttime aircraft activity between 10:00 PM and 7:00 AM to account for the greater potential for nighttime disturbance. Federal land-use compatibility guidance also uses DNL when evaluating aircraft-noise exposure around airports
TOUCH-AND-GO OPERATIONS
Touch-and-go operations are commonly used in flight training to allow pilots to practice repeated takeoffs and landings efficiently.
A standard traffic pattern includes an upwind leg, crosswind leg, downwind leg, base leg, and final approach. Depending on runway direction and operating conditions, pilots may use left-hand or right-hand traffic patterns.
Traffic patterns can change based on the number of aircraft in the pattern, aircraft speed, weather, runway use, safety requirements, and the need to safely separate aircraft; requiring that controllers extend the patterns further north or south.
Centennial Airport’s voluntary noise-abatement guidance encourages flight-training activity to remain within recommended areas when conditions allow. Safety and air traffic control instructions always take precedence.
VOLUNTARY NOISE ABATEMENT
Centennial Airport and CACNR support voluntary operating practices intended to reduce aircraft-noise impacts on surrounding communities when safety, weather, and air traffic control requirements allow.
The 2025 Noise Abatement Guidelines provide recommended practices for propeller aircraft, jets, helicopters, flight training, and touch-and-go activity. They also identify noise-sensitive areas surrounding Centennial Airport.
Recommendations include limiting consecutive touch-and-go operations, reducing unnecessary power where practical, avoiding identified noise-sensitive areas when possible, and avoiding flight-training and ILS-training operations during identified nighttime hours.
In all cases, safety and air traffic control instructions take precedence.
NOISE MONITORING
Noise monitoring provides additional information about how aircraft activity is experienced in communities surrounding Centennial Airport.
Noise data can be considered alongside aircraft operations, complaint information, flight patterns, weather conditions, and other factors to provide additional context for community noise concerns.
Noise monitoring is one of several tools used to better understand aircraft-noise activity and changing conditions around the Airport.
PART 150 NOISE COMPATIBILITY STUDY
Centennial Airport’s Part 150 Noise Compatibility Study is a federal planning process focused on aircraft-noise exposure and land-use compatibility around the Airport.
The study evaluates aircraft-noise conditions and considers potential measures intended to improve compatibility between Airport operations and surrounding communities.
Noise Exposure Maps are part of the Part 150 planning process and illustrate modeled aircraft-noise exposure in relation to surrounding land uses.
