U.S. Department

of Transportation


Federal Aviation



Air Traffic


A Communication from the  Director of Air Traffic                        



        Issue # 2001 - 5

        July 2001                                                                                             

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Position Determination, Scanning, and Coordination


/*TER/  Position determination, scanning, and coordination often seem to generate the majority of comments during on-the-job training (OJT) sessions in an air traffic control tower (ATCT).  Errors associated with position determination, scanning, and coordination probably contribute to most of the delays in ATCT position certifications for developmental controllers.  Errors in these three items are most likely causal or contributory in most controller errors in an ATCT.  While it is obvious that position determination, scanning, and proper coordination are essential for local and ground controllers, others in an ATCT can assist in these areas; everyone in the ATCT should assist.  Every ATCT team member should try to maintain some situational awareness and overview of what is happening on nearby positions, especially during light  traffic periods.

Position determination and scanning are fundamental for controllers.  Most controllers have experienced that horrible feeling during OJT when an aircraft is not where we may expect it to be.  Most OJT instructors have seen a developmental controller look out of the wrong window or toward the wrong fixed base operator or taxiway when an aircraft calls.  Every developmental local controller has probably lost sight of an aircraft that they should have been able to see easily.  It is embarrassing to have to ask a pilot to “say position” when we know that we should be able to see the aircraft.  It is far more embarrassing to guess the position, or give operating instructions without position verification and find out that we were wrong. 


Scanning can save some of those embarrassing situations; however, when any doubt exists, ask the question and positively verify the position.  FAAO 7110.65, Paragraph 3‑1‑7, Position Determination, requires that air traffic control determine the position of an aircraft before issuing taxi instructions or takeoff clearance.  Although an aircraft’s position may be determined visually by the controller, by questioning pilots, or through the use of the airport surface detection equipment, most controllers will agree that there is no substitute for visual observation.  Looking out of the window is a required ATCT controller skill.


Position determination and scanning are duties best shared by everyone in an ATCT.  Most experienced controllers have, at some time during their career, either warned another controller or have been warned when aircraft or equipment were not where they should be.  FAAO 7110.65, Paragraph 3-1-12, Visually Scanning Runways, states, “Local controllers shall visually scan runways to the maximum extent possible” and “Ground control shall assist local control in visually scanning runways, especially when runways are in close proximity to other movement areas.”  These are the requirements, however, everyone in an ATCT should assist with position determination and scanning as they are able.


Clearance delivery (CD), flight data (FD), and other controllers can often keep track of ground control (GC) or local control (LC) traffic by scanning and listening.  Alerts from a controller working FD or CD have prevented many errors and incidents; a controller working a noncontrol position should be a real asset during a busy session on LC/GC.  A controller working the FD/CD position can sometimes see overtakes, cutoffs in the pattern and lost aircraft on taxiways, especially when a LC/GC is busy giving progressive or corrective instructions to other pilots. 


Positive coordination is another of those required controller skills.  This is another area where an ATCT team with good operational teamwork can reduce the chance for error.  Effective LC and GC coordination between positions significantly reduces the chance of movement area incursions.  Coordination is not accomplished until all requirements of the FAA directives (national and local) are complete.  FD/CD controllers can point out the fact that the LC/GC coordination was not complete or has not been accomplished when appropriate.   

Air traffic control is a difficult job.  Position determination, scanning, and coordination are items that can be satisfactorily accomplished by individual controllers, but are more easily accomplished and ensured by an effective controller team.  Effective operational teamwork in these three areas can be the difference between an individual controller struggling to separate observed traffic and a professional team ensuring a safe, efficient, and effective flow of aircraft and vehicles.  An effective operational team can significantly reduce some of the stress and difficulties of a difficult job. (ATP-120)

                                    Questions/comments about content should be addressed to ATP-100