|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||airport : atl|
|Altitude||msl bound lower : 2000|
msl bound upper : 2000
|Controlling Facilities||tower : atl|
|Operator||common carrier : air carrier|
|Make Model Name||Medium Large Transport, Low Wing, 2 Turbojet Eng|
|Navigation In Use||Other|
|Route In Use||approach : visual|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Experience||flight time last 90 days : 150|
flight time total : 12000
flight time type : 2000
|Function||controller : local|
|Qualification||controller : non radar|
|Anomaly||other anomaly other|
|Independent Detector||other controllera|
|Primary Problem||Flight Crew Human Performance|
|Air Traffic Incident||other|
We were cleared for a visual approach to a north side runway by approach control. In the midst of completing checklists, choppy air and possible wake turbulence induced autothrottle surges, I glanced at the approach page to double check the tower frequency. Since we were landing on the north side complex, my quick glance at a busy time in the cockpit picked up the numbers in the north location of the frequency box at the top of the chart page. I used this frequency for initial check in with the tower. It was a time of light traffic, frequencys were not overloaded, the tower corrected the situation, and no problems occurred. But this situation focused my interest on this type of situation. The following is presented in the interest of decreasing the odds of a misreading occurring, perhaps at a busy time when it might cause a problem. How are multiple frequencys displayed on the approach pages at airports with dual side operations, and is there a standard? A quick check of some key airport approach charts suggests that there does not appear to be a standard for dealing with this situation. There are many different airports with dual frequency operations--there are many different ways of presenting the information. It appears that frequency presentation on approach charts for some airports is consistent with mapping standards. Geographic mapping (including the plan view on approach charts) uses the standard convention of north at the top, east on the right, south on the bottom and west on the left. This has been the convention for centuries and is ingrained at a subconscious level in our minds. Following are examples of some current techniques used for display of frequencys in the communications box at the top left corner of approach pages, with comparisons to mapping conventions. Lax uses 'north complex' at top and 'south complex' at bottom, so is consistent with map usage. Phx uses runway numbering, but locates them consistent with map usage. Dfw uses 'east,' 'west' terminology, but opp to mapping conventions has 'east' on the left and 'west' on the right. Atl uses runway numbering. However, it lists the north side runways in the 'south' position, and the south side runways in the 'north' position. Ord and stl use 'north' and 'south,' but place them left and right rather than above and below, thus the axis of presentation is off 90 degrees. Rdu and dtw use 'east' and 'west' terminology (dtw uses '(east)' '(west)'), but opp to mapping conventions have 'east' on the left and 'west' on the right. Each airport has its own unique combination of layout and situation. For this and other reasons, it probably cannot be said today that there is a right way and a wrong way to display frequencys. Finding a best solution will likely involve more research. The remaining questions/comments might be thought of as idea generators for anyone who might like to take a closer look. For this situation, is a standard needed? Might consistency with accepted geographical orientation be a unifying concept to help in the development of such a standard? If a such standard could be developed, might it bring one more detail into consistency with human embedded natural view? In a world with a lot of big problems, does this seem like a small point? Are there examples in history and research that have pointed up situations where even minor inconsistencies can turn small details into major consequences?
Original NASA ASRS Text
Title: ACR MLG CALLED TWR ON THE WRONG FREQ AFTER HANDOFF FROM APCH CTLR. ACFT WAS MAKING A VISUAL APCH TO ATL.
Narrative: WE WERE CLRED FOR A VISUAL APCH TO A N SIDE RWY BY APCH CTL. IN THE MIDST OF COMPLETING CHKLISTS, CHOPPY AIR AND POSSIBLE WAKE TURB INDUCED AUTOTHROTTLE SURGES, I GLANCED AT THE APCH PAGE TO DOUBLE CHK THE TWR FREQ. SINCE WE WERE LNDG ON THE N SIDE COMPLEX, MY QUICK GLANCE AT A BUSY TIME IN THE COCKPIT PICKED UP THE NUMBERS IN THE N LOCATION OF THE FREQ BOX AT THE TOP OF THE CHART PAGE. I USED THIS FREQ FOR INITIAL CHK IN WITH THE TWR. IT WAS A TIME OF LIGHT TFC, FREQS WERE NOT OVERLOADED, THE TWR CORRECTED THE SITUATION, AND NO PROBS OCCURRED. BUT THIS SITUATION FOCUSED MY INTEREST ON THIS TYPE OF SITUATION. THE FOLLOWING IS PRESENTED IN THE INTEREST OF DECREASING THE ODDS OF A MISREADING OCCURRING, PERHAPS AT A BUSY TIME WHEN IT MIGHT CAUSE A PROB. HOW ARE MULTIPLE FREQS DISPLAYED ON THE APCH PAGES AT ARPTS WITH DUAL SIDE OPS, AND IS THERE A STANDARD? A QUICK CHK OF SOME KEY ARPT APCH CHARTS SUGGESTS THAT THERE DOES NOT APPEAR TO BE A STANDARD FOR DEALING WITH THIS SITUATION. THERE ARE MANY DIFFERENT ARPTS WITH DUAL FREQ OPS--THERE ARE MANY DIFFERENT WAYS OF PRESENTING THE INFO. IT APPEARS THAT FREQ PRESENTATION ON APCH CHARTS FOR SOME ARPTS IS CONSISTENT WITH MAPPING STANDARDS. GEOGRAPHIC MAPPING (INCLUDING THE PLAN VIEW ON APCH CHARTS) USES THE STANDARD CONVENTION OF N AT THE TOP, E ON THE RIGHT, S ON THE BOTTOM AND W ON THE LEFT. THIS HAS BEEN THE CONVENTION FOR CENTURIES AND IS INGRAINED AT A SUBCONSCIOUS LEVEL IN OUR MINDS. FOLLOWING ARE EXAMPLES OF SOME CURRENT TECHNIQUES USED FOR DISPLAY OF FREQS IN THE COMS BOX AT THE TOP LEFT CORNER OF APCH PAGES, WITH COMPARISONS TO MAPPING CONVENTIONS. LAX USES 'N COMPLEX' AT TOP AND 'S COMPLEX' AT BOTTOM, SO IS CONSISTENT WITH MAP USAGE. PHX USES RWY NUMBERING, BUT LOCATES THEM CONSISTENT WITH MAP USAGE. DFW USES 'E,' 'W' TERMINOLOGY, BUT OPP TO MAPPING CONVENTIONS HAS 'E' ON THE LEFT AND 'W' ON THE RIGHT. ATL USES RWY NUMBERING. HOWEVER, IT LISTS THE N SIDE RWYS IN THE 'S' POS, AND THE S SIDE RWYS IN THE 'N' POS. ORD AND STL USE 'N' AND 'S,' BUT PLACE THEM LEFT AND RIGHT RATHER THAN ABOVE AND BELOW, THUS THE AXIS OF PRESENTATION IS OFF 90 DEGS. RDU AND DTW USE 'E' AND 'W' TERMINOLOGY (DTW USES '(E)' '(W)'), BUT OPP TO MAPPING CONVENTIONS HAVE 'E' ON THE LEFT AND 'W' ON THE RIGHT. EACH ARPT HAS ITS OWN UNIQUE COMBINATION OF LAYOUT AND SITUATION. FOR THIS AND OTHER REASONS, IT PROBABLY CANNOT BE SAID TODAY THAT THERE IS A RIGHT WAY AND A WRONG WAY TO DISPLAY FREQS. FINDING A BEST SOLUTION WILL LIKELY INVOLVE MORE RESEARCH. THE REMAINING QUESTIONS/COMMENTS MIGHT BE THOUGHT OF AS IDEA GENERATORS FOR ANYONE WHO MIGHT LIKE TO TAKE A CLOSER LOOK. FOR THIS SITUATION, IS A STANDARD NEEDED? MIGHT CONSISTENCY WITH ACCEPTED GEOGRAPHICAL ORIENTATION BE A UNIFYING CONCEPT TO HELP IN THE DEVELOPMENT OF SUCH A STANDARD? IF A SUCH STANDARD COULD BE DEVELOPED, MIGHT IT BRING ONE MORE DETAIL INTO CONSISTENCY WITH HUMAN EMBEDDED NATURAL VIEW? IN A WORLD WITH A LOT OF BIG PROBS, DOES THIS SEEM LIKE A SMALL POINT? ARE THERE EXAMPLES IN HISTORY AND RESEARCH THAT HAVE POINTED UP SITUATIONS WHERE EVEN MINOR INCONSISTENCIES CAN TURN SMALL DETAILS INTO MAJOR CONSEQUENCES?
Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.