Airport Operations 101

​​​Daily operations at an airport are divided into two groups: airside operations and landside operations. This webpage concentrates on airside operations, meaning airport operations that take place within the airport security fence and on the airfield.

Midway Airport Runways

Chicago Midway International Airport (Midway) has 5 runways which are listed below. The runway numbers are magnetic compass headings that an aircraft landing or taking off would use, so a runway numbered 9-2​7 faces east to west (compass heading of 90° and 270°).

  • 4L-22R
  • 4R-22L
  • 13L-31R
  • 13C-31C
  • 13R-31L


Midway Aircraft Operations

Click here to see an exhibit depicting annual aircraft operations at Midway.

Midway Helicopter Operations

Helicopter operations at Midway (both helicopter arrivals and helicopter departures) and their associated noise impacts are tracked by our Airport Noise Management System. Click here to see an exhibit depicting locations of Midway helicopter operations.

Helicopters are only regulated by the Midway Air Traffic Control Tower (Midway Tower) if the helicopters fly into or out of Midway. Other helicopter operations within the Chicago metropolitan airspace are regulated by an FAA office called the DuPage Flight Standards District Office (FSDO).

Click here for more information about the FAA DuPage FSDO.

Prevailing Winds

Aircraft take off and land into the prevailing winds. FAA Air Traffic Control determines which runway will be used based on wind and other weather conditions as well as ground conditions, such as runway closures due to periodic maintenance. At Midway, the primary runways face east to west. In east flow, aircraft depart the primary runways to the east; arriving aircraft approach from the west. Generally, east flow conditions occur during periods of inclement weather. Conversely, in west flow, aircraft depart the primary runways to the west and arrivals come from the east.

Due to prevailing winds, the FAA Air Traffic Control Tower can sometimes use the same runways for an extended period of time. At times one may notice a shift in the way airplanes fly over an area, and this is usually because the “flow” has changed and different runways are in use.

Runway usage is primarily dictated by the prevailing winds, although it is important to note that winds aloft can vary in speed and direction from winds at ground level. During calm wind conditions and air traffic permitting, it is not uncommon for FAA Air Traffic Control to approve a pilot's request to depart in the opposite direction. This is done in accordance with FAA Order JO 7110.65W.

Air Traffic Control

The Federal Aviation Administration (FAA) and the pilot-in-command of each aircraft have sole jurisdiction and responsibility for flight paths. Accordingly, only the FAA has enforcement capability over these issues. The Chicago Department of Aviation has no authority or control over aircraft in flight.

According to the FAA, helicopters have no minimum altitude requirements when weather, safety, and other air traffic permit. See Federal Aviation Regulations (FAR) Part 91.119​.

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