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Tower — Traffic Information and Visual Separation Last updated: 2017-12-02

1. Traffic Information

Often you will need to issue traffic information to pilots to assist visual separation or general pilots’ situation awareness. Describe the relative position of traffic in an easy to understand manner, such as “to your right” or “ahead of you.” It is common to use traffic pattern legs and position from a runway as your reference.

“Traffic, U.S. Air MD-Eighty on downwind leg to your left.”
“King Air inbound from outer marker on straight-in approach to runway one seven.”
“A 737 American on 5-mile final to runway 25L.”

When using a Certified Tower Radar Display (CTRD), you may issue traffic advisories using the standard radar phraseology prescribed as described in the next section.

{Reference: FAAO 7110.65 3-1-6 “Traffic information.”}

2. Position Determination and Use of Tower Radar Displays

The greatest part of a local controller’s workload is looking out the window and visually scanning the runways and airport area to keep the situation awareness. At some locations, however, there are additionally installed tower radar displays aimed to assist local controllers in keeping the situation awareness. There are two types of tower radar displays: uncertified and certified.

a. Uncertified tower radar displays serve only as an additional quick reference for local controllers to maintain general situation awareness. The standard VRC “Tower” radar mode may be used to simulate an uncertified tower radar display workstation. Radar services and radar traffic advisories are not 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.”

“Follow the aircraft ahead of you passing the river at the stacks.”
“King Air passing left to right.”

b. Certified tower radar displays (CTRDs) are considered to be installed at all vZLA class B, C, and D towers. The standard VRC “Tower” radar mode may be used to simulate CTRD. Certified tower radar displays provide additional benefits to local controllers. They can be used for the following purposes:

1. To determine an aircraft’s identification, exact location, or spatial relationship to other aircraft.

On VATSIM, controllers have the ability to view all the possible data about any aircraft on their scope right away. In the real world, however, it’s a little more complicated. Before a simple blip in space becomes an aircraft with a name and a datablock, controllers have to identify it; or in other words, mark it out from a general picture. To simulate this, VATSIM controllers follow the same radar identification procedures used in the real world. The methods of radar identification available to local controllers include the following:

(a) Observing a departing aircraft target within 1 mile of the takeoff runway end. (Useful for identifying any departure that you’ve cleared for takeoff and subsequently observe departing the assigned runway on CTRD display.)

(b) Observing a target whose position with respect to a fix or a visual reporting point corresponds with a direct position report received from an aircraft, and the observed track is consistent with the reported heading or route of flight. (Useful for identify arrivals in instrument or visual approaches that report their position in relation to an instrument approach fix or distance from the airport.)

“Los Angeles Tower, UPS259, over LIMMA, ILS 25L.”
“Los Angeles Tower, Pilatus 123SX, 5 mile final, visual 24R.”

(c) Request the aircraft to activate the “IDENT” feature of the transponder and then observe the identification display. (Can be used for identifying transitioning VFR aircraft. This method does not require a specific code to be assigned. The aircraft may remain squawking VFR as long as you can identify it by the flashing “ID” in the datablock.)


“Los Angeles Tower, Bonanza 2519X, south of the airport for full-stop.”
Note that the position report isn’t specific enough to satisfy the provisions of subpara (b).
“Bonanza 2519X, Los Angeles tower, ident”
”Bonanza 2519X, cleared to enter Los Angeles Bravo airspace, etc.”

(d) Request the aircraft to change to a specific discrete or nondiscrete code, as appropriate, and then observe the target or code display change. (Can be used for identifying transitioning VFR aircraft. Similar to subpara (d.)

SQUAWK (code).

“Los Angeles Tower, Cessna 31ER, north of the airport, request mini-route transition.”
Note that the position report isn’t specific enough to satisfy the provisions of subpara (b).
“Cessna 31ER, Los Angeles tower, squawk 7151”
”Cessna 31ER, cleared through Los Angeles Bravo surface area, etc.”

Tower radar displays are intended to be an aid to local controllers in meeting their responsibilities to the aircraft operating on the runways or within the surface area. They are not intended to provide radar benefits to pilots (such as radar vectors or radar separations). In addition, since local controllers must devote the majority of their time to visually scanning the runways and local area; they cannot be expected to continuously scan the radar screen at the same time. Therefore, since the requirements of the FAAO 7110.65 section 5-3-1 “Application” cannot be assured (local controllers may not dedicate sufficient time to consistently scanning the radar display), the radar functions prescribed above are not considered to be radar services and pilots should not be advised of being in “radar contact.”

2. To provide aircraft with radar traffic advisories. Radar traffic advisories may be issued to radar identified aircraft, and aircraft that have not been radar identified. The latter may happen if you’re aware of the general location of the aircraft being issued a traffic advisory, and deem that the other (radar identified) aircraft is pertinent to the aircraft in that location.

(a) To radar identified aircraft (request that both, the aircraft being provided the traffic advisory, and the aircraft being referenced to be radar identified):

(1) Azimuth from aircraft in terms of the 12-hour clock.
(2) Distance from aircraft in miles.
(3) Direction in which traffic is proceeding and/or relative movement of traffic.

Relative movement includes closing, converging, parallel same direction, opposite direction, diverging, overtaking, crossing left to right, crossing right to left.

(4) If known, type of aircraft and altitude.

TRAFFIC, (number) O’CLOCK,
or when appropriate,
(direction) (number) MILES, (direction)-BOUND and/or (relative movement),
and if known,
(type of aircraft and altitude).
or when appropriate,
(type of aircraft and relative position), (number of feet) FEET ABOVE/BELOW YOU.
If altitude is unknown,

“Traffic, one o’clock, eight miles, opposite direction, Learjet 45, at 2,300 and descending.”
“Traffic, twelve o’clock, five miles, opposite direction, altitude unknown.”

(5) Inform the pilot that traffic is no factor when the traffic you have issued is not reported in sight.


(b) To aircraft that are not radar identified (only request the aircraft being referenced to be radar identified):

(1) Distance and direction from fix.
(2) Direction in which traffic is proceeding.
(3) If known, type of aircraft and altitude.

TRAFFIC, (number) MILES (direction) OF (airport or fix), (direction)-BOUND, (type of aircraft and altitude),
or if altitude is unknown,

“Traffic 2 miles south of Los Angeles Airport, northbound, a Beech Bonanza at 2,500.”

3. To provide a direction or suggested headings to VFR aircraft as a method for radar identification or as an advisory aid to navigation.

(Identification), PROCEED (direction)-BOUND, (other instructions or information as necessary),
(identification), SUGGESTED HEADING (degrees), (other instructions as necessary).

It is important that the pilot be aware of the fact that the directions or headings being provided are suggestions or are advisory in nature. This is to keep the pilot from being inadvertently misled into assuming that radar vectors (and other associated radar services such as terrain or traffic separation) are being provided when, in fact, they are not.

4. To provide information and instructions to aircraft operating within the surface area for which the tower has responsibility.


5. In addition to the CTRD capabilities, all class B and C towers, and some class D towers are limited approach controls, and provide radar separation between aircraft in their airspace.

{Reference: FAAO 7110.65 3-1-7 “Position determination;” 3-1-9 “Use of tower radar displays;” 2-1-21 “Traffic Advisories.”}

3. Visual separation

Visual separation is commonly used by local controllers to expedite airport operations. In fact, tower is the single control position where visual separation is used more than at any other ATC level. The key thing to remember is that visual separation is a temporary condition, and there must always be some other form of approved separation before and after the application of visual separation.

a. To ensure that other separation will exist, consider aircraft performance, wake turbulence, closure rate, routes of flight, and known weather conditions.

b. Reported weather conditions must allow the aircraft to remain within sight until other separation exists. Although there’s no strict weather minima for when a visual separation can be applied, use your good judgment to evaluate the conditions present at the airport.

c. Do not apply visual separation between successive departures when departure routes and/or aircraft performance preclude maintaining separation.


There are two principles of applying visual separation on a local control level: tower visual separation and pilot visual separation. In either case, the common requirement is that communication must be maintained with at least one of the aircraft involved.

a. The application of tower visual separation requires that the aircraft are visually observed by the tower and visual separation is maintained between the aircraft by the tower. The tower shall not provide visual separation between aircraft when wake turbulence separation is required or when the lead aircraft is a B757.

b. The application of pilot visual separation requires that a pilot sees another aircraft and is instructed to maintain visual separation from the aircraft as follows:
(a) Tell the pilot about the other aircraft including position, direction and, unless it is obvious, the other aircraft’s intention.
(b) Obtain acknowledgment from the pilot that the other aircraft is in sight.
(c) Instruct the pilot to maintain visual separation from that aircraft.
(d) Advise the pilot if the radar targets appear likely to converge.

Issue this advisory in conjunction with the instruction to maintain visual separation, or thereafter if the controller subsequently becomes aware that the targets are merging.
(e) If the aircraft are on converging courses, inform the other aircraft of the traffic and that visual separation is being applied.
(f) If the pilot advises he/she has the traffic in sight and will maintain visual separation from it (the pilot must use that entire phrase), the controller need only “approve” the operation instead of restating the instructions.

TRAFFIC, (position and distance relative to the runway), (type of aircraft), (intentions and other relevant information).
If applicable,
If the answer is in the affirmative,

If the pilot advises he/she has the traffic in sight and will maintain visual separation from it (pilot must use that entire phrase):

If aircraft are on converging courses, advise the other aircraft:
TRAFFIC, (position and distance relative to the runway), (direction)-BOUND or pattern leg, (type of aircraft), HAS YOU IN SIGHT AND WILL MAINTAIN VISUAL SEPARATION.

“Beechjet 2519X, traffic departing runway 25R, a Twin Beech, turning right crosswind over the shoreline, do you have it in sight?”
“Traffic in sight. Beechjet 2519X.”
“Beechjet 2519X, maintain visual separation, runway 24L, cleared for takeoff.”
“Cleared for takeoff 24L, will maintain visual separation. Beechjet 2519X.”
“Twin Beech 129P, traffic departing runway 24L straight-out, a Beechjet, has you in sight and will maintain visual separation.”

{Reference: FAAO 7110.65 7-2-1 “Visual separation.”}

4. Wake Turbulence Cautionary Advisories

a. Issue wake turbulence cautionary advisories and the position, altitude if known, and direction of flight of the heavy jet or B757 to VFR aircraft not being radar vectored but are behind heavy jets or B757s. For example, a VFR aircraft in the traffic pattern instructed to follow a heavy jet or B757 arrival to the runway.

b. Issue cautionary information to any aircraft if in your opinion, wake turbulence may have an adverse effect on it. When traffic is known to be a heavy aircraft, include the word heavy in the description.


CAUTION WAKE TURBULENCE (traffic information)


"United two eighty-two, Los Angeles Tower, wind 240 at 6, runway 24R, cleared to land.  Traffic a heavy triple-seven departing the parallel, caution wake turbulence."

{Reference: FAAO 7110.65 2-1-20 “Wake Turbulence Cautionary Advisories.”}