Federal Aviation Administration in the context of "Douglas DC-8"

The September 11 attacks, colloquially known as 9/11, were four coordinated Islamist terrorist suicide attacks by al-Qaeda against the United States in 2001. Nineteen terrorists hijacked four commercial airliners, then flew one into each of the Twin Towers at the World Trade Center in New York City, and another into the Pentagon, the headquarters of the U.S. Department of Defense, in Arlington County, Virginia. The fourth plane crashed in a rural Pennsylvania field during a passenger revolt. In response to the attacks, the United States waged the global war on terror over decades, to eliminate hostile groups deemed terrorist organizations, and the governments purported to support them.

Ringleader Mohamed Atta flew American Airlines Flight 11 into the North Tower of the World Trade Center complex at 8:46 a.m. Seventeen minutes later at 9:03 a.m., United Airlines Flight 175 hit the South Tower. Both collapsed within an hour and forty-two minutes, destroying the remaining five structures in the complex. American Airlines Flight 77 crashed into the Pentagon at 9:37 a.m., causing a partial collapse. The fourth and final flight, United Airlines Flight 93, was believed by investigators to target either the United States Capitol or the White House. Alerted to the previous attacks, the passengers revolted against the hijackers who crashed the aircraft into a field near Shanksville, Pennsylvania, at 10:03 a.m. The Federal Aviation Administration ordered an indefinite ground stop for all air traffic in U.S. airspace, preventing any further aircraft departures until September 13 and requiring all airborne aircraft to return to their point of origin or divert to Canada. The actions undertaken in Canada to support incoming aircraft and their occupants were collectively titled Operation Yellow Ribbon.

Dallas Fort Worth International Airport (IATA: DFW, ICAO: KDFW, FAA LID: DFW) is the primary international airport serving the Dallas–Fort Worth metroplex and the North Texas region, in the U.S. state of Texas.

It is the largest hub for American Airlines, which is headquartered near the airport, and is the third-busiest airport in the world by aircraft movements and the second-busiest airport in the world by passenger traffic in 2022 and 2023, according to the Airports Council International. As of 2025, it is the eighth-busiest international gateway in the United States and the busiest international gateway in Texas. The hub that American Airlines operates at DFW is the second-largest single airline hub in the world and the United States, behind Delta Air Lines's hub in Atlanta.

Airspace is the portion of the atmosphere controlled by a country above its territory and territorial waters that fall under the country's sovereignty and regulatory control.

Internationally, allocation and management of airspace is coordinated by the International Civil Aviation Organization (ICAO), which was established through the Chicago Convention in 1947 to unify air traffic. ICAO organizes airspace into Flight Information Regions (FIRs) and provides classification guidelines. National authorities, such as the FAA, CAA, or EASA implement rules and regulations for air traffic control, special-use airspace, and enforcement within their own FIRs.

Oklahoma City (/ˌoʊkləˈhoʊmə -/ OH-klə-HOH-mə -⁠), often shortened to OKC, is the capital and most populous city of the U.S. state of Oklahoma. It is the 20th-most populous U.S. city and 8th largest in the Southern United States, with a population of 681,054 at the 2020 census. The Oklahoma City metropolitan area, with an estimated 1.49 million residents, is the largest metropolitan area in the state and 42nd-most populous in the country. It is the county seat of Oklahoma County, with the city limits extending into Canadian, Cleveland, and Pottawatomie counties; however, areas beyond Oklahoma County primarily consist of suburban developments or areas designated rural and watershed zones. Oklahoma City ranks as the tenth-largest city by area in the United States when including consolidated city-counties, and second-largest when such consolidations are excluded. It is also the second-largest state capital by area, after Juneau, Alaska.

Oklahoma City has one of the world's largest livestock markets. Oil, natural gas, petroleum products, and related industries are its economy's largest sector. The city is in the middle of an active oil field, and oil derricks dot the capitol grounds. The federal government employs a large number of workers at Tinker Air Force Base and the United States Department of Transportation's Mike Monroney Aeronautical Center (which house offices of the Federal Aviation Administration and the Transportation Department's Enterprise Service Center, respectively).

In aviation, instrument flight rules (IFR) is one of two sets of regulations governing all aspects of civil aviation aircraft operations; the other is visual flight rules (VFR).

The U.S. Federal Aviation Administration's (FAA) Instrument Flying Handbook defines IFR as: "Rules and regulations established by the FAA to govern flight under conditions in which flight by outside visual reference is not safe. IFR flight depends upon flying by reference to instruments in the flight deck, and navigation is accomplished by reference to electronic signals." It is also a term used by pilots and controllers to indicate the type of flight plan an aircraft is flying, such as an IFR or VFR flight plan.

In air traffic control, an area control center (ACC), also known as a center or en-route center, is a facility responsible for controlling aircraft flying in the airspace of a given flight information region (FIR) at high altitudes between airport approaches and departures. In the US, such a center is referred to as an air route traffic control center (ARTCC).

A center typically accepts traffic from—and ultimately passes traffic to—the control of a terminal control center or another center. Most centers are operated by the national governments of the countries in which they are located. The general operations of centers worldwide, and the boundaries of the airspace each center controls, are governed by the International Civil Aviation Organization (ICAO).

Denver International Airport (IATA: DEN, ICAO: KDEN, FAA LID: DEN), often referred to by locals as DIA, is an international airport in the Western United States, primarily serving metropolitan Denver, Colorado, as well as the greater Front Range Urban Corridor.

Runway 16R/34L, with a length of 16,000 feet (3.03 mi; 4.88 km), is the longest public use runway in North America and the seventh longest on Earth. The airport is 25 miles (40 km) driving distance northeast of Downtown Denver, 19 miles (31 km) farther than the former Stapleton International Airport which DEN replaced; the airport is actually closer to the City of Aurora than central Denver, and many airport-related services, such as hotels, are located in Aurora.

Washington Dulles International Airport (/ˈdʌlɪs/ DUL-iss) (IATA: IAD, ICAO: KIAD, FAA LID: IAD) – commonly known simply as Dulles Airport – is an international airport serving the United States's capital city, Washington, D.C. and its surrounding area. It is located 26 miles (42 km) west of downtown Washington, D.C., in Loudoun and Fairfax counties in Northern Virginia.

Opened in 1962, the airport is named after John Foster Dulles, an influential secretary of state during the Cold War who briefly represented New York in the United States Senate. Operated by the Metropolitan Washington Airports Authority, Dulles occupies 13,000 acres (20.3 sq mi; 52.6 km); IAD ranks third in the United States in terms of land area, after Denver International Airport and Dallas Fort Worth International Airport. The "striking" and "iconic" Eero Saarinen-designed Main Terminal received vast acclaim for its innovative architecture when it was completed and has gone on to win numerous awards.

An orbital spaceflight (or orbital flight) is a spaceflight in which a spacecraft is placed on a trajectory where it could remain in space for at least one orbit. To do this around the Earth, it must be on a free trajectory which has an altitude at perigee (altitude at closest approach) around 80 kilometers (50 mi); this is the boundary of space as defined by NASA, the US Air Force and the FAA. To remain in orbit at this altitude requires an orbital speed of ~7.8 km/s. Orbital speed is slower for higher orbits, but attaining them requires greater delta-v. The Fédération Aéronautique Internationale has established the Kármán line at an altitude of 100 km (62 mi) as a working definition for the boundary between aeronautics and astronautics. This is used because at an altitude of about 100 km (62 mi), as Theodore von Kármán calculated, a vehicle would have to travel faster than orbital velocity to derive sufficient aerodynamic lift from the atmosphere to support itself.

Due to atmospheric drag, the lowest altitude at which an object in a circular orbit can complete at least one full revolution without propulsion is approximately 150 kilometres (93 mi).

John F. Kennedy International Airport (IATA: JFK, ICAO: KJFK, FAA LID: JFK) is a major international airport serving New York City and its metropolitan area. JFK Airport is located on the southwestern shore of Long Island, in Queens, New York City, bordering Jamaica Bay. It is the busiest of the seven airports in the New York airport system, the sixth-busiest airport in the United States, and the busiest international commercial airport in North America. The airport, which covers 5,200 acres (2,104 ha), is the largest in the New York metropolitan area. Over 90 airlines operate from JFK Airport, with nonstop or direct flights to destinations on all six permanently inhabited continents.

JFK Airport is located in the Jamaica neighborhood of Queens, 16 miles (26 km) southeast of Midtown Manhattan. The airport features five passenger terminals and four runways. It is primarily accessible by car, bus, shuttle, or other vehicle transit via the JFK Expressway or Interstate 678 (Van Wyck Expressway), or by train. JFK is a hub for American Airlines and Delta Air Lines as well as the primary operating base for JetBlue. The airport is also a former hub for Braniff, Eastern, Flying Tigers, National, Northeast, Northwest, Pan Am, Seaboard World, Tower Air, and TWA.