Chapter 3. Airport Traffic Control- Terminal

Section 1. General

3-1-1. PROVIDE SERVICE

Provide airport traffic control service based only upon observed or known traffic and airport conditions.

3-1-2. PREVENTIVE CONTROL

Provide preventive control service only to aircraft operating in accordance with a letter of agreement. When providing this service, issue advice or instructions only if a situation develops which requires corrective action.

3-1-3. USE OF ACTIVE RUNWAYS

The local controller has primary responsibility for operations conducted on the active runway and must control the use of those runways. Positive coordination and control is required as follows:

  1. Ground control must obtain approval from local control before authorizing an aircraft or a vehicle to cross or use any portion of an active runway.The coordination must include the point/intersection at the runway where the operation will occur.
  2. When the local controller authorizes another controller to cross an active runway, the local controller must verbally specify the runway to be crossed and the point/intersection at the runway where the operation will occur preceded by the word “cross.”
  3. The ground controller must advise the local controller when the coordinated runway operation is complete. This may be accomplished verbally or through visual aids as specified by a facility directive.
  4. USA/USAF/USN NOT APPLICABLE.  Authorization for aircraft/vehicles to taxi/proceed on or along an active runway, for purposes other than crossing, must be provided via direct communications on the appropriate local control frequency. This authorization may be provided on the ground control frequency after coordination with local control is completed for those operations specifically described in a facility directive.
  5. The local controller must coordinate with the ground controller before using a runway not previously designated as active.

3-1-4. COORDINATION BETWEEN LOCAL AND GROUND CONTROLLERS

Local and ground controllers must exchange information as necessary for the safe and efficient use of airport runways and movement areas. This may be accomplished via verbal means, flight progress strips, other written information, or automation displays. As a minimum, provide aircraft identification and applicable runway/intersection/taxiway information as follows:

  1. Ground control must notify local control when a departing aircraft has been taxied to a runway other than one previously designated as active.
  2. Ground control must notify local control of any aircraft taxied to an intersection for takeoff. This notification may be accomplished by verbal means or by flight progress strips.
  3. When the runways in use for landing/departing aircraft are not visible from the tower or the aircraft using them are not visible on radar, advise the local/ground controller of the aircraft's location before releasing the aircraft to the other controller.

3-1-5. VEHICLES/EQUIPMENT/PERSONNEL NEAR/ON RUNWAYS

  1. When established in a letter of agreement (LOA), vehicles, equipment, and personnel in two-way communications with ATC may be authorized to operate in the runway safety area (RSA) up to the edge of the runway surface, which includes when aircraft are arriving, departing, or taxiing along the runway.
  2. Ensure that the runway to be used is free of all known ground vehicles, equipment, and personnel before a departing aircraft starts takeoff or a landing aircraft crosses the runway threshold.

3-1-6. TRAFFIC INFORMATION

  1. Describe vehicles, equipment, or personnel on or near the movement area in a manner which will assist pilots in recognizing them.
  2. Describe the relative position of traffic in an easy to understand manner, such as “to your right” or “ahead of you.”
  3. When using a CTRD, you may issue traffic advisories using the standard radar phraseology prescribed in paragraph 2-1-21, Traffic Advisories.

3-1-7. POSITION DETERMINATION

Determine the position of an aircraft, personnel or equipment before issuing taxi instructions, takeoff clearance, or authorizing personnel, and/or equipment to proceed onto the movement area.

3-1-8. LOW LEVEL WIND SHEAR/MICROBURST ADVISORIES

  1. When low level wind shear/microburst is reported by pilots, Integrated Terminal Weather System (ITWS), or detected on wind shear detection systems such as LLWAS NE++, LLWAS-RS, WSP, or TDWR, controllers must issue the alert to all arriving and departing aircraft. Continue the alert to aircraft until it is broadcast on the ATIS and pilots indicate they have received the appropriate ATIS code. A statement must be included on the ATIS for 20 minutes following the last report or indication of the wind shear/microburst.
  2. At facilities without ATIS, ensure that wind shear/microburst information is broadcast to all arriving and departing aircraft for 20 minutes following the last report or indication of wind shear/microburst.
  3. Apply the following procedures and phraseology for the depicted wind shear detection system described below.
    1. At locations equipped with LLWAS, the local controller must provide wind information as follows:
      1. If an alert is received, issue the airport wind and the displayed field boundary wind.
      2. If multiple alerts are received, issue an advisory that there are wind shear alerts in two/several/all quadrants. After issuing the advisory, issue the airport wind in accordance with paragraph 3-9-1, Departure Information, followed by the field boundary wind most appropriate to the aircraft operation.
      3. If requested by the pilot, issue specific field boundary wind information even though the LLWAS may not be in alert status.
    2. Wind shear detection systems, including TDWR, WSP, LLWAS NE++ and LLWAS-RS provide the capability of displaying microburst alerts, wind shear alerts, and wind information oriented to the threshold or departure end of a runway. When detected, the associated ribbon display allows the controller to read the displayed alert without any need for interpretation.
      1. If a wind shear or microburst alert is received for the runway in use, issue the alert information for that runway to arriving and departing aircraft as it is displayed on the ribbon display.
      2. If requested by the pilot or deemed appropriate by the controller, issue the displayed wind information oriented to the threshold or departure end of the runway.
      3. LLWAS NE++ or LLWAS-RS may detect a possible wind shear/microburst at the edge of the system but may be unable to distinguish between a wind shear and a microburst. A wind shear alert message will be displayed, followed by an asterisk, advising of a possible wind shear outside of the system network.
      4. If unstable conditions produce multiple alerts, issue an advisory of multiple wind shear/microburst alerts followed by specific alert or wind information most appropriate to the aircraft operation.
      5. The LLWAS NE++ and LLWAS-RS are designed to operate with as many as 50 percent of the total sensors inoperative. When all three remote sensors designated for a specific runway arrival or departure wind display line are inoperative then the LLWAS NE++ and LLWAS-RS for that runway arrival/departure must be considered out of service. When a specific runway arrival or departure wind display line is inoperative and wind shear/microburst activity is likely; (for example, frontal activity, convective storms, PIREPs), the following statement must be included on the ATIS, “WIND SHEAR AND MICROBURST INFORMATION FOR RUNWAY (runway number) ARRIVAL/DEPARTURE NOT AVAILABLE.”
  4. Wind Shear Escape Procedures.
    1. If an aircraft under your control informs you that it is performing a wind shear escape, do not issue control instructions that are contrary to pilot actions. ATC should continue to provide safety alerts regarding terrain or obstacles and traffic advisories for the escape aircraft, as appropriate.
    2. Unless advised by additional aircraft that they are also performing an escape procedure, do not presume that other aircraft in the proximity of the escape aircraft are responding to wind shear alerts/events as well. Continue to provide control instructions, safety alerts, and traffic advisories, as appropriate.
    3. Once the responding aircraft has initiated a wind shear escape maneuver, the controller is not responsible for providing approved separation between the aircraft that is responding to an escape and any other aircraft, airspace, terrain, or obstacle. Responsibility for approved separation resumes when one of the following conditions is met:
      1. Departures:
        1. A crew member informs ATC that the wind shear escape maneuver is complete and ATC observes that approved separation has been re-established, or
        2. A crew member informs ATC that the escape maneuver is complete and has resumed a previously assigned departure clearance/routing.
      2. Arrivals:
        1. A crew member informs ATC that the escape maneuver is complete, and
        2. The aircrew has executed an alternate clearance or requested further instructions.

3-1-9. USE OF TOWER RADAR DISPLAYS

  1. Uncertified tower display workstations must be used only as an aid to assist controllers in visually locating aircraft or in determining their spatial relationship to known geographical points. Radar services and traffic advisories are not to be provided using uncertified tower display workstations. General information may be given in an easy to understand manner, such as “to your right” or “ahead of you.”
  2. Local controllers may use certified tower radar displays for the following purposes:
    1. To determine an aircraft's identification, exact location, or spatial relationship to other aircraft.
    2. To provide aircraft with radar traffic advisories.
    3. To provide a direction or suggested headings to VFR aircraft as a method for radar identification or as an advisory aid to navigation.
    4. To provide information and instructions to aircraft operating within the surface area for which the tower has responsibility.
  3. Additional functions may be performed provided the procedures have been reviewed and authorized by appropriate management levels.
  4. If there is an outage of the ASR supporting the ASDE system and Multilateration (MLAT) is inoperative or is not present at airports with an ASDE system, the tower position(s) responsible for aircraft on approach to the airport must enable the ADS-B indicator on the tower display workstation(s) (TDW(s)).

3-1-10. OBSERVED ABNORMALITIES

When requested by a pilot or when you deem it necessary, inform an aircraft of any observed abnormal aircraft condition.

3-1-11. SURFACE AREA RESTRICTIONS

  1. If traffic conditions permit, approve a pilot's request to cross Class C or Class D surface areas or exceed the Class C or Class D airspace speed limit. Do not, however, approve a speed in excess of 250 knots (288 mph) unless the pilot informs you a higher minimum speed is required.
  2. Do not approve a pilot's request or ask a pilot to conduct unusual maneuvers within surface areas of Class B, C, or D airspace if they are not essential to the performance of the flight.

    EXCEPTION. A pilot's request to conduct aerobatic practice activities may be approved, when operating in accordance with a letter of agreement, and the activity will have no adverse effect on safety of the air traffic operation or result in a reduction of service to other users.

3-1-12. VISUALLY SCANNING RUNWAYS

  1. Local controllers must visually scan runways to the maximum extent possible.
  2. Ground control must assist local control in visually scanning runways, especially when runways are in close proximity to other movement areas.

3-1-13. ESTABLISHING TWO-WAY COMMUNICATIONS

Pilots are required to establish two-way radio communications before entering the Class D airspace. If the controller responds to a radio call with, “(a/c call sign) standby,” radio communications have been established and the pilot can enter the Class D airspace. If workload or traffic conditions prevent immediate provision of airport traffic control services, inform the pilot to remain outside the Class D airspace until conditions permit the services to be provided.

3-1-14. GROUND OPERATIONS WHEN VOLCANIC ASH IS PRESENT

When volcanic ash is present on the airport surface, and to the extent possible:

  1. Avoid requiring aircraft to come to a full stop while taxiing.
  2. Provide for a rolling takeoff for all departures.

3-1-15. GROUND OPERATIONS RELATED TO THREE/FOUR-HOUR TARMAC RULE

When a request is made by the pilot-in-command of an aircraft to return to the ramp, gate, or alternate deplaning area due to the Three/Four-Hour Tarmac Rule:

  1. Provide the requested services as soon as operationally practical, or
  2. Advise the pilot‐in‐command that the requested service cannot be accommodated because it would create a significant disruption to air traffic operations.