Noise Management Data
Runway Use Report
The five runways at Midway are utilized at different times primarily depending 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 reasons.
The Runway Use Report presents the average number of daily operations on each runway, the percentage of use for each runway and a 12-month average. The percentage of use for each runway is shown graphically for departures and arrivals. This data is for all hours of the day and night and for all aircraft types during the specified quarter.
Aircraft Noise Report
The Aircraft Noise Report summarizes noise measurements from each of the 12 noise monitors located around the Airport. The data presented summarizes the Day-Night Average Sound 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 quarter and its comparison to the same quarter of the previous year, and it compares the current quarter to the 12-month average. The aircraft noise report identifies noise from the existing aircraft operations at Midway International Airport.
Noise Hotline Report
The Department of Aviation maintains a toll-free noise complaint hotline (1-800-914-8537) for citizens to express their concerns about particular incidents or aircraft noise levels in general. The noise hotline report summarizes the number of calls received. 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 quarter.
Also included are complaint calls by quarter which display seasonal trends in complaints received. Complaint totals for 2007 and beyond only include calls made within the State of Illinois to the Noise Hotline.
Aircraft Fleet Mix Report
The Airline Fleet Mix Report summarizes the number of operations by airline operating at Midway International Airport. The report is summarized in four ways: operations for each airline during all hours of the day; operations for each airline during the nighttime hours (10 p.m. to 7 a.m.); percent of total operations for each airline during all hours of the day and percent of total operations during the nighttime hours. This report displays the average operations at Midway International Airport during the calendar quarter indicated.
The Aircraft Fleet Mix Report summarizes the number and type of aircraft operating at Midway International Airport. The report is summarized in four ways: fleet mix for each airline during all hours of the day; fleet mix for each airline during the nighttime hours (10 p.m. to 7 a.m.); percent of total fleet mix for each aircraft type during all hours of the day and percent of total fleet mix by aircraft type during the nighttime hours. This report displays the average fleet mix at Midway International Airport during the calendar quarter indicated.
In 1990, Congress enacted legislation to eliminate all Stage 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 Midway 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 99% of the operations at Midway International Airport are originally certified as Stage 3 aircraft.
Historical Fly Quiet Program Monthly Reports (2009 and earlier)