Noise Management Data
Runway Use Report
O'Hare has seven runways that are all utilized at different times depending primarily upon the prevailing wind conditions on the airfield, as well as any runway maintenance. Aircraft performance requirements make it necessary for aircraft to depart and land into the wind for safety purposes.
The Runway Use Report presents the average percentage of use for each runway for the current month, the previous month and a 12-month average. The percentage of use for departures and arrivals is shown graphically for each runway. This data is for all hours of the day and for all aircraft types. Also shown is the runway use for the nighttime hours (10 pm to 7 am).
Aircraft Noise Report
The Aircraft Noise Report summarizes noise measurements from each of the 33 noise monitors located around the Airport. The data presented summarizes the Day-Night Average Noise Levels (DNL). DNL is a 24-hour time-averaged sound exposure level with a 10 decibel (dB) nighttime (10 p.m. to 7 a.m.) weighting to account for the lower background noise levels during the nighttime hours.
The data displays the measured aircraft DNL for each month and its comparison to the same month of the previous year, and it compares the current month to the 12-month average. The aircraft noise report identifies noise from the existing aircraft operations at O'Hare. The modeled values for each monitor are shown for 1997, 2000 and the OMP Full Build-Out Noise Contours.
The aircraft noise levels for each monitor vary from month to month. This is primarily due to runways being utilized differently under changing wind conditions which effect where the aircraft fly.
Noise Hotline Report
The Chicago Department of Aviation maintains a toll-free noise hotline (1-800-435-9569) for citizens to express their concern about particular incidents or aircraft noise levels in general. The noise hotline report summarizes the number of calls received and where the callers were located. The tabular report lists the number of calls by community as well as the number of individual callers. The graph at the bottom of the page illustrates the nature of the complaint calls during the specified month.
Effective May 2007, only hotline calls located in Illinois are included in this report.
Aircraft Fleet Mix Report
Operations for all Hours of the Day
The Aircraft Fleet Mix Report summarizes the number and type of aircraft operating at O'Hare International Airport during both all hours of the day and during the nighttime hours.
In 1990, Congress enacted legislation to eliminate all State 2 aircraft operating in the continental United States by the year 2000. In response, the FAA created a program to "phase-out" the older, louder Stage 2 aircraft over a ten-year period to achieve full compliance by the 2000 deadline. As of January 2000, all aircraft operating at O'Hare and within the United States were Stage 3. Stage 3 aircraft, such as the Boeing 757 (B757) and new Boeing 737's (B737) use a quieter type of engine that significantly reduces noise at the source. Also, a Stage 3 aircraft can be a previous Stage 2 aircraft with the engines retrofitted with a "Hush-kit" such as a Boeing 727 (B72Q), Boeing 737-200 (B73Q) and DC-9 (DC9Q). More than 98% of the operations at O'Hare International Airport are originally certified as Stage 3 aircraft.
Historical Fly Quiet Program Monthly Reports (2009 and earlier)