ATC to English Translations

This may take a while, but I thought it might be a good idea to put up some ATC terminology common within the circle but which might not be understood (or be easily misunderstood) in the general population. Following is a list:

Center

An ARTCC (Air Route Traffic Control Center)—a regional facility providing ATC services over thousands of square miles. Each one is divided into dozens of sectors—low altitude (usually up to FL230), high altitude (FL240 and above except when…), super or ultra high (anywhere from FL310 and above all the way up).

Tower

The facility most readily identified as “ATC,” provides separation to aircraft within about five miles of the airport and usually up to 1,000' above the surface. What is commonly thought of by a lay observer as the tower controller is actually called “local controller.” There may be a second local controller, a ground controller (or two), and a clearance delivery. Tower services are inherently visual, although many include radar displays for assistance, as well. Some towers have an Approach Control colocated at the site. Not all airports have towers. Not all towers have an approach control. Not all approach controls are located at the tower.

Approach Control

A facility providing ATC services (principally for IFR aircraft, but busier airports provide separation for VFR aircraft, as well) around one or more airports. Customarily from the ground to 10,000' (excluding the tower’s airspace described above) but lower or higher top altitudes are not uncommon depending on local traffic demands. ATC services inlude arrival as well as departure (and occasional overflight) and the Approach Control is usually subdivided internally with discrete sectors which provide approach control as well as departure control services. Approach controls are usually radar equipped, but not necessarily.

A-side

Assistant controller—both the position and the person working it. Less used since the ’70s as there is less actual control function and more ripping of strips, placing them in holders, and delivering them to the associated sector in the modern architecture.

D-side

Also sometimes called a “manual” controller, responsible for sequencing strips, providing non-radar separation under certain circumstances, and assisting the radar controller with coordination with other sectors/facilities.

R-side

A rarely used term, but the complement to the A-side and D-side. Usually called the “radar man” or the “R position”. In the days before the modern ARTCCs when radar was uncommon, the person who talked to the airplanes was sometimes referred to as the “radio man”.

Radar

• Device used to detect aircraft and render a planform display of their position.
• Display used to present information detected by radar to controllers or other personnel.
• Position in an ATC facility occupied by a controller who employs air traffic control procedures and engages in radio communications with aircraft.
• Contraction of the proper response (“radar contact”) to a transferring controller describing the position of an oncoming aircraft (handoff).

Handoff

The act of communicating to a receiving controller the position and other pertinent information of an aircraft and confirmation from the receiving controller that the appropriate target correlates with the description. Handoff is not synonymous with communications transfer. By the time you’re given a frequency change, you’ve already been handed off. The process is invisible to the user.

Bay

Vertical panel, usually adjacent to a radar scope, which holds strips (19 in an ARTCC). There are (were, since strips seem to have become a tool of the dinosaur and have been replaced by displays) at least two bays and sometimes a third or a partial third and define the D-side position. The strip holders ride on two raised metal bars to keep them aligned. .

Strip

• Paper used to display aircraft flight data and to record instructions to the affected flight.
• Plastic holder of a paper strip.
• Activity sometimes employed by commercial practitioners at controller off-duty gatherings.

Cock

Shift a strip (including plastic holder) to the left or right in the bay to indicate that attention needs to be given the associated flight. Because of the construction and configuration of both strip holders and the bay, the strips are very stable in their position, whether cocked or not.

Rush

A bunch of airplanes—usually predictable, but might happen spontaneously. Sometimes mislabeled as a “push” (sic). Most rushes are of like flights, such as inbound rushes or departure rushes, although it’s not unusual to experience a “rush” of overflight airplanes all destined for the same airport in another facility hundreds or thousands of miles away.

Deal

Unofficial term for when separation becomes less than advertised. Also officially referred to as an Operational Error. Long mislabeled a “System Error” (sic). In ARTCCs, separation is five miles or 1,000 feet. In approach controls, the lateral separation can be three miles. In the tower, visual separation is the norm, although there are lateral parameters used on the runway.

Deviation

• What aircraft request to do to avoid thunderstorms
• Contraction of the term “Operational Deviation” which describes an airspace violation. Potentially as serious as a deal, but little known or understood outside ATC, even in the aviation community generally.

Vector

The act of assigning a heading for an aircraft to fly, taking them off their own navigation. Approach control functions are almost wholly vectoring activities, while center functions are almost wholly not, with the exception of sequencing arrivals for the approach control. That’s not to say ARTCCs don’t vector otherwise—there are many reasons to vector aircraft, up to and including collision avoidance.

Ident

In each (modern) airplane is a transponder—an electronic device that enhances the aircraft’s target on our radar. There’s a button on each one labeled “IDENT” and when it’s pressed, it causes the target on our radar to change for a few seconds (it will bloom noticably or the symbol in a digital system will change to another, clearly different symbol for a few seconds). That’s one of the methods we use to confirm the identity of an aircraft. Our phraseology was to request the aircraft to “ident” and we would watch for the return. In the old days when I hired in, the phraseology was “squawk ident”, however, it was changed to just plain “ident” shortly after I started—probably even before I trained on the radar. On my very last day before retiring, there were controllers who hadn’t been born when “squawk ident” was changed, who were saying it. I’ve written a piece calledlearning by legend,which was a rampant disease in ATC in my later years.

Interestingly, the phraseology was only infrequently used in the last two thirds of my career. In the early days, it was employed on the initial contact of every controller for every airplane in every sector. Pilots might have worn out the “Ident button” over the life of an aircraft. Once automation was able to employ discrete transponder codes for flights we were incrementally able to reduce the requirements for idents.

NBCAP

Related to transponders and automation, the National Beacon Code Allocation Plan was software designed to distribute the nearly 4,100 beacon codes for flight plan usage. Since there were often well more than 4,000 flights in the air at any given moment, sometimes it was necessary to require an aircraft to change their code when they flew into a different facility’s airspace, but thanks to NBCAP, it was increasingly unnecessary. Ultimately, because of the program, it regularly became possible for an aircraft to take off, cruise, and land without ever having to “ident”.

Tracker

(or handoff man) A controller assigned to assist the radar man when traffic warrants more help than just the D-side. We called them “trackers” at ZJX and “handoff men” at ZAU.

Coordinator

A position above and behind a group of sectors. They were/are intermittently used. At ZJX I recall them infrequently manned, and almost always by a supervisor. At ZAU there were seven coordinator positions staffed from approximately 0800 until roughly 2000, and they were regularly staffed by journeyman controllers. The standard operation at ZAU involved making handoffs on inbounds to the associated low altitude sectors and coordinating lower altitudes on same. The advent of RDP (radar data processing—essentially data blocks on radar) eventually obviated the need for such intense coordination. We probably stopped staffing them in the ’80s.

Flow Control

A joke in the ’60s and ’70s, the concept began to mature, particularly in the runup to 1981. A comprehensive Central Flow Control was developed with real procedures and real effects. When I went to Flow Control (by then called the Traffic Management Unit) in 1988, the process was very aggressive and taken very seriously. The goal, at least insofar as the busiest of the base 25 airports managed by CF was concerned, was to reduce airborne holding. We did a lot of airborne holding, and while we at ZAU managed it quite well, facilities that didn’t hold every day were far more vulnerable to errors. Traffic is now managed with delays on the ground rather than airborne holding except as unforecast exigencies demand. Managing arrivals was not the only function—considerable study and negotiation led to preferred routes to avoid local heavy rushes at individual sectors, as well.

Last updated: 22 February 2013