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Left Nav - Air Traffic Organization

Safety and Technical Training

Friday, June 21, 2024

What We Do

The ATO's Safety & Technical Training service unit influences and addresses risk in the NAS through:

  • aligning data-driven changes in the operation
  • modernizing training to educate and prepare the ATO's technical workforce by focusing on timely delivery, operational priorities, and competencies
  • monitoring mitigations and changes in the NAS
  • informing stakeholders of our successful strategies to meet our safety goals

Our safety functions include:

  • event investigation
  • data analysis
  • corrective actions
  • training for over 14,000 air traffic controllers and over 6,000 airway transportation system specialists
  • policy development, performance measurement, and promotion of a positive safety culture

We accomplish this through the combined efforts of our four directorates (Safety, Technical Training, Policy & Performance, and Strategic Outreach), and through strong stakeholder partnerships.

Our Programs

Slot Administration - U.S. Level 3 Airports

When the number of flights increases to a level that creates regular and significant flight delays, and infrastructure improvements to manage the capacity are not feasible in the near future, the airport may be declared a Level 3 airport by the FAA.

In the U.S., the Level 3 airports are John F. Kennedy International Airport (JFK), LaGuardia Airport (LGA), and Ronald Reagan Washington National Airport (DCA).

At DCA, slot controls that are equivalent to Level 3, are in place pursuant to the High Density Rule (14 CFR part 93 subparts K & S) to govern operations daily, from 6:00 am to 11:59 pm. During slot-controlled hours, regularly scheduled operations are limited to 48 per hour by regulation. Some additional operations are permitted by exemption on a limited basis pursuant to 49 U.S.C. §§ 41714 and 41718.

At JFK and LGA, Level 3 slot controls are in place pursuant to FAA Order.

The Slot Administration Office within the Air Traffic Organization's System Operations Services at the FAA is the coordinator for runway slots at the U.S. designated Level 3 airports.

Carriers or other interested parties may contact the Slot Administration Office at the FAA for more information about operations slot rules at slot-controlled airports: 7-awa-slotadmin@faa.gov.

Slot Allocation Process for Level 3 Airports

DCA and LGA are Level 3 airports with primarily domestic or pre-cleared international operations. Allocations are on a continuing basis based on historic slots, a two-month minimum usage requirement, and other provisions in the FAA order and rules.

The U.S. Level 3 airport that generally follows the IATA flight scheduling process, issued in the WSG is JFK. Unlike the other Level 3 airports, JFK has a large percentage of international flights.

Flight schedules under the WSG process are generally divided into two seasons per year—Winter and Summer. Consequently, the slot allocation process occurs twice annually at JFK.

The WSG also includes a set of steps followed to allocate slots for a given season. Currently, this applies in the U.S. only to JFK. The first step generally begins April (for the following Winter season) and September (for the next Summer season):

WSG Steps to Follow to Allocate Slots for Level 3 Airports

  • SHL Deadline
  • Agreed Historics Deadline
  • Initial Submission Deadline
  • AppCall Opened to Coordinators
  • SAL Deadline
  • AppCall Opened to Flight Operators
  • IATA Slot Conference
  • Slot Return Deadline
  • Historics Baseline Date

Step 1: Slot Historic List (SHL) Deadline

This is the first step in the slot allocation process for the season. The SHL Deadline is the date by which the FAA, as coordinator, must provide carriers of the details about the status of historic slots.

Step 2: Agreed Historics Deadline

The Agreed Historics Deadline is the last date for carriers to raise any objections to the FAA's assessment of the historic slots.

Step 3: Initial Submission Deadline

The Initial Submission Deadline is the last date when carriers can submit plans for flight operations in the designated season to receive priority consideration or to claim historic slots. Schedule requests after the Initial Submission Deadline are considered with lower priority. The FAA typically uses the same Initial Submission Deadline as the IATA Slot Conference and announces the seasonal deadline in the Federal Register. The deadlines are typically in May and October.

Step 4: IATA Appointments Calendar (AppCal) opened to Coordinators

AppCal is a calendar application used for the worldwide slot conference. At this step in the process, the FAA has the opportunity to set availability for meetings during the conference or to initiate meetings with carriers or others during the slot conference.

Step 5: SAL (Slot Allocation Listing) Deadline

The SAL Deadline is the date by which the FAA releases the first draft of the slot allocations for the coming season.

Step 6: "AppCal" Open to airlines

At this point, access to the AppCal calendar application is made available to carriers so that they can plan meetings with the FAA and slot coordinators from airports around the world to discuss their slot allocations, schedule plans, or other issues for the coming season.

Step 7: IATA Slot Conference

The Slot conference is held twice yearly, once for each of the scheduling seasons. The conference is convened to allocate slots at Level 3 airports and to discuss schedules and potential schedule adjustments at Level 2 airports. The coordinators and schedule facilitators (the FAA in the U.S. for runway operations) meet individually with carriers to discuss that operator's schedule for the coming season.

Step 8: Slot Return Deadline

The slot return deadline is the date by which carriers must return slots they do not intend to operate during the forthcoming season.

Step 9: Historics Baseline Date

The Historics Baseline Date is the date at which the new slot allocations become effective. This is also the start date used to calculate the usage requirement for allocated slots under the WSG process.

Slot Administration - U.S. Level 2 Airports

Wednesday, November 27, 2024

If delays can be managed with some guidance on the number and timing of flights through schedule facilitation, then an airport may be designated Level 2 by the FAA based primarily on performance metrics and runway capacity. In the U.S., the FAA Slot Administration Office within the Air Traffic Organization facilitates runway schedules at Level 2 airports designated by the FAA.

In the U.S., the Level 2 airports include Chicago O'Hare International Airport (ORD), Los Angeles International Airport (LAX), Newark Liberty International Airport (EWR) (Change of Newark Liberty International Airport Designation, 81 FR 19861 (Oct. 20, 2016)) and San Francisco International Airport (SFO). An airport operator may separately declare an airport as Level 2 based on airport passenger terminal facility or other constraints.

Currently, the four FAA Level 2 airports have a separate process for flights operating at specific airport facilities designated and managed by the local airport operator. In these cases, carriers provide schedules to the FAA and the local airport schedule facilitators. The carrier is responsible for ensuring matching runway and terminal approvals. Additionally, some international passenger terminals are Level 2 at non-FAA Level 2 designated airports and managed at the local airport level. Those airports are currently Orlando International Airport (MCO) and Seattle-Tacoma International Airport (SEA).

WSG Steps to Follow for Slot Facilitation for Level 2 Airports

  • Initial Submission Deadline
  • AppCall Opened to Coordinators
  • SAL Deadline
  • AppCall Opened to Flight Operators
  • IATA Slot Conference
  • Slot Return Deadline

The roles of the facilitator at a Level 2 airport and the coordinator in a Level 3 airport as outlined in the WSG are administratively similar, but both are governed by different principles for managing scheduling processes. Schedule facilitation at Level 2 airports is designed to engender collaboration and gain mutual agreement between the parties regarding schedules and potential adjustments to stay within the performance goals and capacity limits of the airport, and to mitigate delays and congestion that would result in the need for Level 3 slot controls.

Although voluntary, carriers are expected to seek and obtain schedule approval in the Level 2 process, as schedule facilitation is used to prevent an escalation in congestion necessitating a possible Level 3 designation. If a carrier chooses to operate a flight without approval from the FAA and the airport subsequently transitions into Level 3 status, the carrier would not receive priority for any flights not approved by the facilitator when the Level 3 historic baseline is established. This could ultimately result in the carrier being unable to continue similar service.

The FAA tracks flight operations closely at Level 2 airports in the U.S., monitoring for time periods that may be susceptible to systemic volume-related delays as a result of congestion.

The process for schedule facilitation of Level 2 airports follows many of the same steps as Level 3 airports.

Instead of submitting historic slot data, each flight operator submits a proposed schedule for the "Initial Submission Deadline," which is then analyzed, along with all of the submissions, for the potential to create delays.

The "SAL Deadline" is when the FAA returns the schedules with any proposed changes or comments.

Carriers have the opportunity to meet directly with the FAA at the IATA slot conference to discuss potential schedule changes, just as carriers at Level 3 airports do.

The "Slot Return Deadline" for Level 2 is the opportunity for the carriers to remove any potential flights they do not intend to operate in the coming season.

Carriers may contact the FAA Slot Administration Office for more information about runway review of operations at schedule-facilitated airports: Slot Administration

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.