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Left Nav - Air Traffic Organization

Slot Administration - Schedule Facilitation

When airport infrastructure is generally unable to meet carrier demand, the FAA may impose mandatory slot coordination or engage in schedule facilitation with carriers in order to ensure the efficient use of the airspace consistent with the FAA's authority in 49 U.S.C. § 40103(b). A slot is an FAA authorization to conduct an operation (either one take-off or one landing) at a constrained airport during a specific time period. A slot is allocated in accordance with FAA rules or orders in effect for the specific airport.

The International Air Transport Association (IATA) manages the Worldwide Slot Guidelines (WSG) to provide the global air transport community with uniform standards for the management of airport slots at coordinated airports and planned operations at facilitated airports. The FAA generally follows the standards and process established in the WSG for slot administration to the extent there is no conflict with U.S. law, rules, or other administrative procedures.

Under the WSG, airports are classified into one of three categories based on the degree of congestion and potential for delays:

  • Level 1 is assigned where the capacity of airport infrastructure is generally adequate to meet demand and therefore there is no extensive pattern of delays;
  • Level 2 is assigned where there is potential for congestion during some periods of the day, which can be managed through mutual cooperation of the carriers with the schedule facilitator to ensure scheduling within the airport's capacity; and
  • Level 3 is assigned where infrastructure is inadequate to meet demand and there is significant potential for delays requiring mandatory slot controls.

As the agency charged with ensuring the safety and efficiency of the National Airspace System (NAS), the FAA administers the coordination of slots and facilitation of schedules that align with the policy goals established relative to performance goals and runway capacity at airports within the slots program.

However, carriers must also separately work with local airport authorities to obtain access to passenger terminals and gates.

Although most airports in the U.S. are categorized as Level 1 airports under the IATA WSG, the FAA has imposed Level 3 slot controls by rule at some of the most congested airports in the country.

Slot Administration - Slot Allocation Process

Slot administration in the U.S. generally follows the process laid out by IATA in the WSG. This process requires a coordinator for each Level 3 airport and a schedule facilitator for each Level 2 airport. The FAA fills that role at U.S. airports where the FAA establishes the need for runway limitations or formal schedule review. Separately, local airport authorities may review certain flights based on airport terminal capacity.

Flight schedules are generally divided into seasons per year—Winter and Summer. Consequently, the slot allocation and schedule facilitation process occurs twice annually for EWR, JFK, LAX, ORD, and SFO. DCA and LGA slot allocation rules provide for continuing allocation and those airports do not follow the seasonal WSG allocation.

The process relies heavily on "historic slots," or slots that carriers have operated for a qualifying duration under the FAA rules or orders. The carriers submit their schedules or slot requests, and the FAA responds to their proposal.

Slot Administration - Slot Definition

In the context of airport coordination, a slot is an authorization to either take-off or land at a particular airport on a particular day during a specified time period. This authorization is for a planned aircraft operation and is distinct from air traffic control clearance or similar authorizations. Slots, or limits on the planned aircraft operations, are a tool used in the United States and around the world to manage air traffic at extremely busy airports, and to prevent repeated delays that result from too many flights trying to take off or land at the same time.

Around the world, airports are designated at levels indicating their degree of congestion. Level 1 airports have sufficient capacity to meet demand. Level 2 airports may have some periods when demand approaches one or more capacity limits, but a voluntary schedule-facilitation process prevents systemic delays. Level 3 airports have demand for airport infrastructure that significantly exceeds the airport's capacity during the relevant periods and without controls, would have unacceptable systemic delays. Level 3 airports are under slot control and require advance approval to operate during slot controlled hours.

National Airway Systems Engineering, Operational Support Directorate

Our Mission

We provide national software, hardware, technical documentation, scientific and direct engineering support for operational National Airspace System (NAS) equipment. We support surveillance, navigation, and infrastructure facilities to ensure safe, reliable, and efficient operations. For assigned systems, the AJW workforce serves as the agency's premiere level of system expertise available.

Mode S/Digitizers/SBSM

Our Mission

Provide second level engineering support and serve as the Office of Primary Responsibility (OPR) for assigned commissioned National Airspace System (NAS) systems. Our services support the safety mission within the FAA Administrator's Strategic Plans and Goals in field support, engineering modifications, software updates and releases, engineering support, and documentation support.


Our Mailing Address

William J. Hughes FAA Technical Center
AJW-145, Building 270
Atlantic City International Airport
Atlantic City, NJ 08405

Spectrum Engineering & Policy

The Federal Aviation Administration (FAA) Spectrum Engineering is responsible for ensuring that the radio frequency spectrum needs of both military and civil aviation are met.

The aviation community is one of the major users of the radio frequency spectrum in the United States. In fact, the top three spectrum users in the Federal Government are the FAA, the Air Force, and the Navy — the FAA presently has over 30,137 frequency assignments. Virtually all of the FAA's navigation, communication, and surveillance systems are dependent on use of the radio frequency spectrum. Numerous aircraft systems, such as airborne weather radar, are also users of the spectrum.

Spectrum Engineering & Policy

Spectrum engineers are involved from "cradle-to-grave" in nearly all aviation systems. OMB Circular A-11 and DOT Order 5420.3 require that radio frequency spectrum be available before developing or procuring new communications-electronics systems.

Other Responsibilities Include

  • Pre-development — Spectrum engineers assist in determining the proper frequency band for proposed equipment and applicable standards.
  • Development and Production — Spectrum engineers play a key role in testing to ensure that equipment meets specifications for electromagnetic compatibility and radiation hazards criteria. FAA's Technical Center, under the Spectrum Engineering Services' guidance, provides valuable assistance in addressing these issues.
  • Operation — The Regional frequency management offices engineer site-specific radio frequencies for approval by Director of Spectrum Engineering Services. Regional frequency management offices also perform the detailed on-site investigations needed to resolve cases of radio frequency interference.

FAA Weather Cameras

Tuesday, February 18, 2025

The FAA Weather Camera Program improves aviation safety and efficiency by providing pilots with near real-time visual weather data. Pilots, dispatchers, Flight Service Specialists, and National Weather Service (NWS) forecasters receive visual confirmation of weather conditions at airports, mountain passes, and other strategic locations along air routes and areas with elevated accident rates.

Weather cameras give users near real-time images (updated every 10 minutes) of weather conditions prior to takeoff and during flight, via en route weather updates. Multiple camera views are available at each weather camera location. When combined with available textual weather products, weather camera images become a powerful “go-or-no-go” aviation flight decision tool.

Implementation of the weather camera service across the State of Alaska resulted in an 85% reduction in weather-related accidents and a 69% reduction in weather-related flight interruptions from 2007-2014.

The Weather Camera Program currently owns and maintains over 260 camera systems in Alaska, Hawaii, and CONUS. They also host camera images from over 530 non FAA-owned weather camera sites in Alaska, Hawaii, CONUS, and Canada. Current plans call for the installation of 160 new FAA camera sites in Alaska and the Continental U.S. by 2031, and to expand its third-party camera networks by over 100 sites per year.

View weather camera map and images.

Third Party Hosted Information

Advance aviation in your area with Weather Cameras!

An investment in the weather cameras benefits aviation:

  • Reduces weather-related aviation accidents
  • Reduces weather-related flight interruptions
  • Improves aviation flight decision making
  • Enhances Flight Service operations

The FAA helps achieve this goal:

  • Provides technical specifications from proven technology
  • Provides guidance with site selection
  • Connects cameras to existing FAA network infrastructure
  • Hosts camera images on the existing website https://weathercams.faa.gov
  • Leverages existing FAA infrastructure

Please contact WCAMExp@faa.gov to advance aviation safety with weather camera technology.

Contact Us

Friday, May 03, 2024

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