O'Hare International Airport (IATA: ORD, ICAO: KORD, FAA LID: ORD), typically referred to as O'Hare Airport, Chicago O'Hare, or simply O'Hare, is an international airport located on the Northwest Side of Chicago, Illinois, 14 miles (23 km) northwest of the Loop business district; operated by the Chicago Department of Aviation^[7] and covering some 7,627 acres (3,087 ha)^[4], O'Hare has non-stop flights to 228 destinations in North America, South America, Europe, Africa, Asia and Oceania.^[8][9]

Designed to be the successor to Chicago's "busiest square mile in the world", Midway Airport, O'Hare began as an airfield serving a Douglas manufacturing plant for C-54 military transports during World War II. It was named for Edward "Butch" O'Hare, the U.S. Navy's first Medal of Honor recipient during that war.^[10] Later, at the height of the Cold War, O'Hare served as an active fighter base for the Air Force.^[11]

As the first major airport planned after World War II, O’Hare's innovative design pioneered concepts such as concourses, direct highway access to the terminal, jet bridges, and underground refueling systems.^[12] It became famous as the first World's Busiest Airport of the jet age, holding that distinction from 1963 to 1998; today, it is the world's sixth-busiest airport, serving 83 million passengers in 2018.^[13]

O'Hare is unusual in that it serves as a major hub for more than one of the three U.S. mainline carriers; it is a large hub for both United Airlines (which is headquartered in Chicago) and American Airlines.^[14][15] It is also a focus city for Frontier Airlines and Spirit Airlines.^[2][3]

While Terminals 2 and 3 remain of the original design, the airfield has seen radical modernization, and the terminal complex is beginning an expansion of passenger facilities that will remake it as North America's first airport built around airline alliances.^[16][17]

Not long after the opening of Midway Airport in 1926, the City of Chicago realized that additional airport capacity would be needed in the future. The city government investigated various potential airport sites during the 1930s, but made little progress prior to America's entry into World War II.^[10]

O'Hare's place in aviation began with a manufacturing plant for Douglas C-54s during WWII. The site was then known as Orchard Place, and had previously been a small German-American farming community. The 2,000,000 square feet (190,000 m2) plant, located in the northeast corner of what is now the airport property, needed easy access to the workforce of the nation's second-largest city, as well as its extensive railroad infrastructure and location far from enemy threat. Some 655 C-54s were built at the plant, more than half of all produced. The attached airfield, from which the completed planes were flown out, was known simply as Douglas Airport; initially, it had four 5,500-foot (1,700 m) runways.^[10] Less known is the fact that it was the location of the Army Air Force's 803rd Specialized Depot,^[18] a unit charged with storing many captured enemy aircraft. A few representatives of this collection would eventually be transferred to the Smithsonian Institution's National Air and Space Museum.^[19][20]

Douglas Company's contract ended with the war's conclusion and, though consideration was given to building commercial aircraft at Orchard, the company ultimately chose to concentrate commercial production at its original headquarters in Santa Monica, CA.^[10] With the departure of Douglas, the complex took the name of Orchard Field Airport, and was assigned the IATA code ORD.^[21]

The United States Air Force used the field extensively during the Korean War, at which time there was still no scheduled commercial service at the airport. Although not its primary base in the area, the Air Force used O'Hare as an active fighter base; it was home to the 62nd Fighter-Interceptor Squadron flying F-86 Sabres from 1950 to 1959.^[11] By 1960, the need for O'Hare as an active duty fighter base was diminishing, just as commercial business was picking up at the airport. The Air Force removed active-duty units from O'Hare and turned the station over to Continental Air Command, enabling them to base reserve and Air National Guard units there.^[22] As a result of a 1993 agreement between the City and the Department of Defense, the reserve based was closed on April 1, 1997, ending its career as the home of the 928th Airlift Wing. At that time, the 357 acre (144 ha) site came under the ownership of the Chicago Department of Aviation.^[23]

In 1945, Chicago mayor Edward Kelly established a formal board to choose the site of a new facility to meet future aviation demands. After considering various proposals, the board decided upon the Orchard Field site, and acquired most of the federal government property in March 1946. The military retained a relatively small parcel of property on the site, and the rights to use 25% of the airfield's operating capacity for free.^[10]

Ralph H. Burke devised an airport master plan based on the pioneering idea of what he called "split finger terminals", allowing a terminal building to be attached to "airline wings" (concourses), each providing space for gates and planes. (Pre-war airport designs had favored ever-larger single terminals, exemplified by Berlin's Tempelhof.) Burke's design also included underground refueling, direct highway access to the front of terminals, and direct rail access, all of which are utilized at airports worldwide today. O'Hare was the site of the world's first jet bridge in 1958,^[24][25] and successfully adapted slip form paving, developed for the nation's new Interstate highway system, for seamless concrete runways.

In 1949, the City renamed the facility O'Hare Field to honor Edward "Butch" O'Hare, the U.S. Navy's first flying ace and Medal of Honor recipient in World War II.^[26] Its IATA code (ORD) remained unchanged, however, resulting in O'Hare's being one of the few IATA codes bearing no connection to the airport's name or metropolitan area.^[21]

Scheduled passenger service began in 1955,^[27] but growth was slow at first. Although Chicago had invested over $25 million in O'Hare, Midway remained the world's busiest airport and airlines were reluctant to move until highway access and other improvements were completed.^[28] The April 1957 Official Airline Guide listed 36 weekday departures from the airport, while Midway coped with 414. Improvements began to attract the airlines: O'Hare's first dedicated international terminal opened in August 1958, and by April 1959 the airport had expanded to 7,200 acres (2,900 ha) with new hangars, terminals, parking and other facilities. The expressway link to downtown Chicago, now known as the Kennedy Expressway, was completed in 1960.^[27] And new Terminals 2 and 3, designed by C. F. Murphy and Associates, opened on January 1, 1962.^[29]

The biggest factor driving the airlines to O'Hare from Midway was the jet airliner; the first scheduled jet at O'Hare was an American 707 from New York to Chicago to San Francisco on 22 March 1959.^[30] One-mile-square Midway did not have space for the runways that 707s and DC-8s required. Airlines had been reluctant to move to O'Hare, but they were equally unwilling to split operations between the two airports: in July 1962 the last fixed-wing scheduled airline flight in Chicago moved from Midway to O'Hare. The arrival of Midway's traffic quickly made O'Hare the world's busiest airport, serving 10 million passengers annually. Within two years that number would double, with Chicagoans proudly boasting that more people passed through O'Hare in 12 months than Ellis Island had processed in its entire existence. O'Hare remained the world's busiest airport until 1998.

In the 1980s, after passage of US airline deregulation, the first major change at O'Hare occurred when TWA left Chicago for St. Louis as its main mid-continent hub.^[31] Although TWA had a large hangar complex at O'Hare and had started Constellation nonstops to Paris in 1958, by the time of deregulation its operation was losing $25 million a year under intense competition from United and American.^[32] Northwest likewise ceded O'Hare to the competition and shifted to a Minneapolis and Detroit-centered network by the early 1990s after acquiring Republic Airlines in 1986.^[33] Delta maintained a Chicago hub for some time, even commissioning a new Concourse L in 1983.^[34] Ultimately, Delta found competing from an inferior position at O'Hare too expensive and closed its Chicago hub in the 1990s, concentrating its upper Midwest operations at Cincinnati.

The dominant hubs established at O'Hare in the 1980s by United and American continue to operate today. United developed a new two-concourse Terminal 1 (dubbed "The Terminal for Tomorrow"), designed by Helmut Jahn. It was built between 1985 and 1987 on the site of the original Terminal 1; the structure, which includes 50 gates, is best known for its curved glass forms and the connecting underground passage between Concourses B and C.^[35] American renovated and expanded its existing facilities in Terminal 3 from 1987 to 1990; these renovations feature a flag-lined entrance hall to Concourses H/K.^[36][36]

The demolition of the original Terminal 1 in 1984 to make way for Jahn's design forced a "temporary" relocation of international flights into facilities called "Terminal 4" on the ground floor of the airport's central parking garage. International passengers were then bused to and from their aircraft. Relocation finally ended with the completion of the 21-gate International Terminal in 1993 (now called Terminal 5); it contains all customs facilities. Its location, on the site of the original cargo area and east of the terminal core, necessitated the construction of the Airport Transit System people-mover, which connected the terminal core with the new terminal as well as remote rental and parking lots.^[34]

The large consolidating mergers in the airline industry from 2008 to 2014 left O'Hare's domestic operations simplified: the airport found itself primarily with United mainline in Terminal 1, United Express, Air Canada and Delta in Terminal 2, and American and smaller carriers in Terminal 3.

O'Hare's high volume and crowded schedule, along with the vagaries of weather in the upper Midwest, frequently led to major delays; its hub status meant delays could affect airlines system-wide, causing issues for air travel across North America. Official reports at the end of the 1990s ranked O'Hare as one of the worst performing airports in the United States based on the percentage of delayed flights.^[37] The situation was exacerbated by a practice known as banking, in which regional and mainline flights arrive within several narrow windows during each day (facilitating quick transfers but creating temporary congestion); the situation illustrated the bitter competition between United and American, who combined for 86% of all operations but refused to cooperate to ease the situation. In 2004, facing the imposition of flight limits at O'Hare by the Federal Aviation Administration, United and American agreed to modify their flight schedules to help reduce congestion caused by clustered arrivals and departures, mainly by adjusting the schedules of their regional carriers.^[38]

While reducing the practice of banking helped, the reality was that the airfield had remained unchanged since the addition of its last new runway (4R/22L) in 1971.^[39] O'Hare's three pairs of angled runways were meant to allow takeoffs into the wind, but they came at a cost: the various intersecting runways were both dangerous and inefficient. In 2001, the Chicago Department of Aviation committed to an O'Hare Modernization Plan (OMP). Initially estimated at $6.6 billion, the OMP was to be paid by bonds issued against the increase in the federal passenger facility charge enacted that year as well as federal airport improvement funds.^[40] The modernization plan was approved by the FAA in October 2005 and involved a complete reconfiguration of the airfield.

The OMP included the construction of four new runways, the lengthening of two existing runways, and the decommissioning of three old runways to provide O'Hare with six parallel runways and two crosswind runways. This was a complete redesign of Burke's basic airfield structure; O'Hare had effectively functioned in a circular manner, with the terminal complex in the center and runways around it.^[10] Now, O'Hare would be organized into three sections, north to south: the north airfield, containing three east-west runways, one crosswind runway, and a new cargo area; the terminal complex and ground transportation access in the center; and the south airfield, again containing three east-west runways, a crosswind runway, and a large cargo area. Construction of the two new airfield layouts and the new cargo area, while the space-constrained airport continued full operations, presented significant time and capacity challenges. The north airfield gained runway 9L/27R in 2008, while the south airfield saw the opening of runway 10C/28C in 2013 and runway 10R/28L in 2015.

The OMP was the subject of lengthy legal battles, both with suburbs who feared the new layout's noise implications as well as survivors of persons interred in a cemetery the city proposed to relocate; some of the cases were not resolved until 2011.^[16] These, plus the reduction in traffic as a result of the 2008 financial crisis, delayed the OMP's completion; construction of the sixth and final parallel runway (9C/27C)^[41] began in 2017. Its completion in 2020, along with an extension of runway 9R/27L to be completed in 2021, will conclude the OMP.^[42]

Although construction continues, peak capacity (number of operations/hour) has already increased by 50% and total (all weather) system delays reduced by 57%;^[43] after completion of the first two phases of the OMP, on-time arrivals improved from 67.6% to 80.8%.^[44] By 2017, O'Hare ranked 14th in on-time performance of the top 30 U.S. airports.^[45] Costs of the O'Hare Modernization Plan had risen, by 2015, beyond $8 billion.^[46]

In 2018, the city and airlines legally committed to Phase I of a new Terminal Area Plan dubbed O'Hare (or ORD) 21.^[17] It marks the first comprehensive redevelopment and expansion of the terminal core in O'Hare's history. ORD21 will enable same-terminal transfers between international and domestic flights, faster connections, improved facilities and technology for TSA and customs inspections and much larger landside amenities like shopping and restaurants. A principal feature of the plan is the reorganization of the terminal core into an "alliance hub", the first in North America; airside connections and layout will be optimized around airline alliances. This will be made possible by the construction of the O’Hare Global Terminal (OGT) where Terminal 2 currently stands. The OGT and two new satellite concourses will allow for expansion for both American's and United's international operations as well as easy interchange with their respective Oneworld (American) and Star Alliance (United) partner carriers, eliminating the need to exit the secured airside, ride the ATS, and re-clear security at Terminal 5. Under the reconfiguration, United and its Star Alliance partners will utilize Terminal 1 and the OGT, American and its Oneworld partners will use the OGT and Terminal 3, and Delta and its SkyTeam partners, as well as non-affiliated carriers, will relocate to Terminal 5.

The plan is set to add over 3,000,000 square feet (280,000 m2) to the airport's terminals, a new customs processing center in the OGT, reconstruction of gates and concourses (new concourses will be a minimum of 150 feet (46 m) wide), increase the gate count from 185 to 235, and provide 25% more ramp space at every gate throughout the airport to accommodate larger aircraft.^[47] Since construction of the OGT cannot interfere with ongoing operations at the airport, it is scheduled to take place in stages, with the first step (scheduled to begin 2019) being to dig the tunnel that will connect the terminal core with two new satellite concourses.^[48] Demolition of Terminal 2 and the subsequent construction of the OGT can only proceed after the completion of the two new satellite concourses, which will provide the gates lost by the demolition of Terminal 2. By terms of the agreement, total costs of $8.5 billion (current as of 2019) for ORD21 are to be borne by bonds issued by the City, which will be retired by airport usage fees paid by the airlines. ORD21 is scheduled for completion in 2028.^[49]

Construction has begun on the first major phase of ORD21, the expansion of Terminal 5, to be substantially completed in 2022. This expansion will not only add ten gates and passenger amenities, but will also convert Terminal 5 into a mixed domestic/international terminal in preparation for Delta/SkyTeam's relocation, scheduled for 2022, and the construction of the OGT.

After an international design competition that featured public voting on five final architectural proposals, the Studio ORD group, led by architect Jeanne Gang, was selected to design the OGT,^[50][51] while Skidmore, Owings & Merrill will design Satellites 1 & 2.^[52]

O'Hare has four numbered passenger terminals with nine lettered concourses and a total of 191 gates. ^[53]

With the exception of flights from airports with U.S. Customs and Border Protection preclearance, all inbound international flights arrive at Terminal 5, as the other terminals do not have customs screening facilities. Several alliance partners, such as ANA, Iberia, Japan Airlines, and Lufthansa, have outbound international flights departing from Terminals 1 and 3. This requires that the aircraft arrive and discharge passengers at Terminal 5, after which the empty plane is towed to another terminal for boarding. This is to expedite connections for passengers transferring from domestic flights to those outbound international flights; while Terminals 1, 2, and 3 all allow airside connections, Terminal 5 is separated from the other terminals by a set of taxiways that cross over the airport's access road, requiring passengers to exit security, ride a shuttle bus, and then re-clear security before boarding.

Terminal 1, containing Concourses B & C, is home to United Airlines flights, including all mainline flights and some United Express operations, as well as some departures for Star Alliance partners Lufthansa and ANA.

Concourses B and C are linear concourses located in separate buildings parallel to each other. Concourse B is adjacent to the airport roadway and houses passenger check-in, baggage claim, and security screenings on its landside and aircraft gates on its airside. Concourse C is a satellite terminal with gates on all sides, in the middle of the ramp, and is connected to Concourse B via an underground pedestrian tunnel under the ramp. The tunnel originates between gates B8 and B9 in Concourse B, and ends on Concourse C between gates C17 and C19. The tunnel is illuminated with a neon installation titled Sky's the Limit (1987) by Canadian artist Michael Hayden, which plays an airy and very slow-tempo version of Rhapsody in Blue.

United operates three United Clubs in Terminal 1. For premium international passengers, United operates a Polaris Lounge and a United Arrivals Suite.^[54]

Terminal 2, containing Concourses E & F, houses Air Canada, Alaska Airlines, Delta and Delta Connection domestic flights, JetBlue,^[55] and most United Express operations (although United check-ins take place in Terminal 1). The terminal contains a Delta Sky Club and a United Club.

Terminal 3, containing Concourses G, H, K & L, houses all departing and domestic arriving American and American Eagle flights, as well as departures for Oneworld carriers Iberia and Japan Airlines and unaffiliated carriers.

Concourses G and L house most American Eagle operated flights, while Concourses H and K house American's mainline operations. American's Oneworld partners Japan Airlines and Iberia depart from K19 or K16. Concourse L is also used by non-affiliated airlines Air Choice One, Cape Air, and Spirit.^[56] A new "stinger" extension of Concourse L, with five new American regional gates, opened to service in May, 2018.^[57]

American has three Admirals Club locations in Terminal 3. For premium international passengers, American operates a Flagship Lounge.^[58]

Terminal 5, containing Concourse M, houses all of O'Hare's international arrivals (excluding flights with Air Canada, American and United from airports with U.S. border preclearance). Other destinations with preclearance, including flights operated by Aer Lingus and Etihad Airways, arrive at Terminal 5 but are treated as domestic arrivals. With the exception of select Star Alliance and Oneworld flights that board from Terminal 1 or Terminal 3 respectively, all non-U.S. carriers except Air Canada depart from Terminal 5.

The first effects of ORD21 can be seen by developments at Terminal 5: in 2018, Frontier Airlines became the first domestic carrier to move operations to Terminal 5, and the expansion of Terminal 5 began in March 2019 at the eastern end of the M concourse.^[59] It is not expected to interfere with passenger operations.^[60]

Several airlines have lounges in Terminal 5, including Air France – KLM, British Airways, Korean Air, SAS, and SWISS; there is also a multi-carrier Swissport Lounge. The airport's U.S. Customs and Border Protection facility is located on the arrival (lower) level.

O'Hare has two sets of parallel runways, one on either side of the terminal complex. The north airfield has two parallel east-west runways (9L/27R and 9R/27L), with 9C/27C scheduled for completion in 2020. The south airfield, where the O'Hare Modernization Program (OMP) is largely complete, has three parallel east-west runways (10L/28R, 10C/28C, and 10R/28L). Two parallel runways are oriented northeast/southwest (4R/22L, 4L/22R), one on each side of the airport. The north crosswind runway, 4L/22R, intersects 9R/27L and forthcoming 9C/27C, limiting its use;^[61] however, runway 22L is often used for takeoffs during what is called "west flow" on the main runways. Each side of the airfield has its own ground control tower.

Original runway 18/36 closed in 2003, and runway 14L/32R closed in 2015. The last of the runways to close under the OMP, originally 14R/32L, was decommissioned on March 29, 2018, and the FAA Airport Diagram now designates the remaining sections^[62] as taxiway SS.^[63] In 1956, it had been the first runway added to the old Douglas Field layout (8,000 feet long when originally constructed) and was lengthened to 11,600 feet and rebuilt with concrete in 1960 to became O'Hare's first full-length jet runway.^[10]

O'Hare has a voluntary nighttime (22:00–07:00) noise abatement program.^[64]

Currently, passengers are shuttled between the terminal core (Terminals 1 – 3), Terminal 5, and the remote lots and new Multi-Modal Facility (MMF) via free shuttle buses; buses board on the lower level of each terminal and run every 5–10 minutes, 24 hours a day. The Bus Shuttle center, located on the main floor of the parking garage opposite terminals 1–3, provides a temporary boarding location for local hotel shuttles and regional public transport buses.^[65]

Normally, such transfers would be made using the 2.5 mi (4 km)-long automated Airport Transit System (ATS), which connects all four terminals landside and the rental and remote parking lots. However, the ATS is undergoing a $310 million modernization and expansion that includes replacing the existing 15-car fleet with 36 new Bombardier vehicles, upgrading the previous infrastructure, and extending the line 2,000 feet (610 m) to the MMF.^[66][67] As of January 8, 2019, the ATS was removed from service to allow for completion and testing of the project.^[68]

The new MMF opened in October 2018 and is the home of all on-airport car rental firms as well as some extended parking. Rental customers now proceed from the terminal to the MMF via shuttle bus.^[69] After the completion of the ATS project in late 2019, it is anticipated that all shuttle bus service to the terminals will end, eliminating some 1.3 million bus trips yearly. In addition, the Chicago-area commuter rail system, Metra, has a transfer station of its North Central Service (NCS) located at the northeast corner of the MMF; however, the NCS currently operates a occasional schedule on weekdays only.^[70]

The CTA Blue Line's north terminus is at O'Hare and provides direct service to downtown via the Dearborn Street subway in the Loop and continuing to west suburban Forest Park. Trains depart at intervals ranging from every 4 to 30 minutes, 24 hours a day.^[71] The station is located on the lower level of the parking garage, and can be accessed directly from Terminals 1–3 via tunnel and from Terminal 5 via shuttle bus.

About 23,000 parking spaces are available at O'Hare. A large multi-level garage containing short-term parking is located immediately opposite the terminal core, and there is a short-term lot immediately in front of Terminal 5. There are also several economy lots available; these are located farther away but are accessed from the terminals with free shuttle bus service. Rates at airport lots currently range from $10 to $40 a day.^[72]

O'Hare is directly served by Interstate 190, which offers interchanges with Mannheim Road (U.S. 12 and 45), the Tri-State Tollway (Interstate 294), and Interstate 90. I-90 continues as the Kennedy Expressway into downtown Chicago and becomes the Jane Addams Memorial Tollway northwest to Rockford and the Wisconsin state line.

The Hilton Chicago O'Hare is between the terminal core and parking garage and is currently the only hotel on airport property. It is owned by the Chicago Department of Aviation and operated under an agreement with Hilton Hotels, who extended their agreement with the city by ten years in 2018.^[73]

There are presently two main cargo areas at O'Hare. The South Cargo Area was relocated in the 1980s from the airport's first air cargo facilities, which were located east of the terminal core, where Terminal 5 now stands. Many of the structures in this new cargo area then had to be rebuilt, again, to allow for the OMP and specifically runway 10R/28L; as a result, what is now called the South Cargo Area is located between 10R/28L and 10C/28C. These facilities were established mainly by traditional airline-based air cargo; Air France Cargo, American, JAL Cargo, KLM, Lufthansa Cargo, Northwest and United all built purpose-built, freestanding cargo facilities,^[74] although some of these are now leased out to dedicated cargo firms. In addition, the area contains two separate facilities for shipper FedEx and one for UPS.^[74]

The Northeast Cargo Area (NEC) is a conversion of the former military base (the Douglas plant area) at the northeast corner of the airport property. It is a new facility designed to increase O'Hare's cargo capacity by 50%. Two buildings currently make up the NEC: a 540,000 square feet (50,000 m2) building completed in 2016,^[75] and a 240,000 square feet (22,000 m2) building that was completed in 2017.^[76] A third structure will complete the NEC with another 150,000 square feet (14,000 m2) of warehouse space.^[77]

The current capability of the cargo areas provide 2,000,000 square feet (190,000 m2) of airside cargo space with parking for 40 wide-body freighters matched with over 2,000,000 square feet (190,000 m2) of landside warehousing capability. O'Hare shipped over 1.8 million tonnes of cargo in 2018, third among major airports in the U.S.^[78]

The USO offers two facilities: one open 24 hours and located before security in Terminal 2, and an additional site behind security in Terminal 3, open 06:00–22:30 daily. Each offers meals, refreshments, TV and quiet rooms, and internet access. Active duty military personnel and their families, as well as new recruits going to Recruit Training Command, are welcome.^[79]

The large Postal Service processing facility at O'Hare is located at the far south end of the airfield along Irving Park Road. Being on secured airfield property, it is not open to the public. USPS drop locations are provided in Terminals 1, 3 and 5.

Notes:

In 2011, O'Hare became the first major airport to build an apiary on its property; every summer, it hosts as many as 75 hives and a million bees. The bees are maintained by 30 to 40 ex-offenders with little to no work experience and few marketable skills; they are primarily recruited from Chicago's North Lawndale neighborhood. They are taught beekeeping but also benefit from the bees' labor, turning it into bottled fresh honey, soaps, lip balms, candles and moisturizers marketed under the beelove product line; products are sold at stores and used by restaurants throughout both Chicago airports, as well as available online.^[168].^[169] More than 500 persons have completed the program, transferring to jobs in manufacturing, food processing, customer service, and hospitality; the repeat-offender rate is reported to be less than 10%.^[170]

O'Hare has used livestock since 2013 in its Sustainable Vegetation Management initiative to control vegetation in 11.5 acres of hard-to-reach areas such as steep banks along a creek on the airport property. A mix of goats, sheep, llamas, alpacas, and even a donkey named Jackson control buckthorn, garlic mustard, ragweed and various other invasive species. The livestock assist not only with vegetation removal and control, but also reduce hiding and nesting places for birds that may interfere with safe aircraft operations; all without any food expense or environmental damage.^[171]

The following is a list of major crashes or incidents that happened to planes at O'Hare, on approach, or just after takeoff from the airport.^[172]