Narrative:

I recall being given runway 21L, but did not write down the clearance. I do not recall reading back the clearance, but did tell ground that I was unfamiliar with the airport (and the taxiway structure). I was instructed to taxi straight ahead out of the transient area, and then turn left onto the taxiway to runway 21L. I guess I was depending on ground for guidance in the unfamiliar situation. I proceeded out of the transient area, but did not immediately recognize the taxiway, as it is very narrow, and the runway (21L) just beyond is wide and easily seen. Confusing the runway with the taxiway, I proceeded toward the runway, but then recognized my mistake and stopped. At the same instant, ground called, telling me to stop. At that point, I was shocked to see a departing plane on runway 21L whizzing past, not very far away, and realized how close that mistake had taken me. I do not believe I ever crossed that hold short line. I told ground I had mistaken the runway for the taxiway, turned, and entered the taxiway toward runway 21L. Being distracted by one mistaken action, I apparently did not remember being told to hold short of runway 12, and continued on the taxiway (it is only a very short distance) until being told by ground to halt, that I was in violation of the hold short line of runway 12. I was told to hold in place for quite a few mins, and then cleared to taxi to runway 21L as desired. I may have been just on or across the hold short line, but I am certain that I was well short of the runway itself. I did not observe any traffic on or for runway 12. Before departure, I was asked to telephone the tower on my arrival, which I did. The structure of the txwys and runways in that area is very confusing for someone unfamiliar with the airport. Neither the airways facility directory nor the government approach plates (both of which I consulted before flying into prescott) have an airport diagram that is useful at this point. The airport diagram should be published, and the entrance directly onto runway 21L from the transient area should be closed to prevent the confusion I experienced. The airport facility directory cites runway 21L as the designated calm wind runway. The winds were calm. Runway 21L was in use. Traffic seemed to be light. I believe most student training activity uses runway 21R. On my arrival in prescott the previous day, I had been cleared to taxi to the transient area with no mention of the intersecting runway 12. On a calm, light traffic day, I cannot imagine why runway 12 should be in use at all. I see no use for runway 12 except when needed because of high xwinds on runway 21L. The numbering of runways 21 and 12 is itself confusing. It is easy to mistake a transposition of the 2 digits. In tucson, my home base, the same situation has been rectified by renumbering what should actually be runway 12L as runway 11L. The heading is really 123 degrees. I suggest that prescott should renumber runway 12 as runway 11 instead, to reduce possible confusion. Once ground had seen that I was experiencing difficulty with one taxiway/runway situation, I think they could have been much more helpful in guiding me in taxiing runway 12, with advice before I reached the hold short line, not waiting until after a violation. In the future, I shall be extremely careful about understanding clrncs, especially in unfamiliar sits.

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Original NASA ASRS Text

Title: PLT UNFAMILIAR WITH ARPT COMES CLOSE TO TAXIING ONTO 2 DIFFERENT RWYS WITHOUT CLRNC.

Narrative: I RECALL BEING GIVEN RWY 21L, BUT DID NOT WRITE DOWN THE CLRNC. I DO NOT RECALL READING BACK THE CLRNC, BUT DID TELL GND THAT I WAS UNFAMILIAR WITH THE ARPT (AND THE TXWY STRUCTURE). I WAS INSTRUCTED TO TAXI STRAIGHT AHEAD OUT OF THE TRANSIENT AREA, AND THEN TURN L ONTO THE TXWY TO RWY 21L. I GUESS I WAS DEPENDING ON GND FOR GUIDANCE IN THE UNFAMILIAR SIT. I PROCEEDED OUT OF THE TRANSIENT AREA, BUT DID NOT IMMEDIATELY RECOGNIZE THE TXWY, AS IT IS VERY NARROW, AND THE RWY (21L) JUST BEYOND IS WIDE AND EASILY SEEN. CONFUSING THE RWY WITH THE TXWY, I PROCEEDED TOWARD THE RWY, BUT THEN RECOGNIZED MY MISTAKE AND STOPPED. AT THE SAME INSTANT, GND CALLED, TELLING ME TO STOP. AT THAT POINT, I WAS SHOCKED TO SEE A DEPARTING PLANE ON RWY 21L WHIZZING PAST, NOT VERY FAR AWAY, AND REALIZED HOW CLOSE THAT MISTAKE HAD TAKEN ME. I DO NOT BELIEVE I EVER CROSSED THAT HOLD SHORT LINE. I TOLD GND I HAD MISTAKEN THE RWY FOR THE TXWY, TURNED, AND ENTERED THE TXWY TOWARD RWY 21L. BEING DISTRACTED BY ONE MISTAKEN ACTION, I APPARENTLY DID NOT REMEMBER BEING TOLD TO HOLD SHORT OF RWY 12, AND CONTINUED ON THE TXWY (IT IS ONLY A VERY SHORT DISTANCE) UNTIL BEING TOLD BY GND TO HALT, THAT I WAS IN VIOLATION OF THE HOLD SHORT LINE OF RWY 12. I WAS TOLD TO HOLD IN PLACE FOR QUITE A FEW MINS, AND THEN CLRED TO TAXI TO RWY 21L AS DESIRED. I MAY HAVE BEEN JUST ON OR ACROSS THE HOLD SHORT LINE, BUT I AM CERTAIN THAT I WAS WELL SHORT OF THE RWY ITSELF. I DID NOT OBSERVE ANY TFC ON OR FOR RWY 12. BEFORE DEP, I WAS ASKED TO TELEPHONE THE TWR ON MY ARR, WHICH I DID. THE STRUCTURE OF THE TXWYS AND RWYS IN THAT AREA IS VERY CONFUSING FOR SOMEONE UNFAMILIAR WITH THE ARPT. NEITHER THE AIRWAYS FACILITY DIRECTORY NOR THE GOV APCH PLATES (BOTH OF WHICH I CONSULTED BEFORE FLYING INTO PRESCOTT) HAVE AN ARPT DIAGRAM THAT IS USEFUL AT THIS POINT. THE ARPT DIAGRAM SHOULD BE PUBLISHED, AND THE ENTRANCE DIRECTLY ONTO RWY 21L FROM THE TRANSIENT AREA SHOULD BE CLOSED TO PREVENT THE CONFUSION I EXPERIENCED. THE ARPT FACILITY DIRECTORY CITES RWY 21L AS THE DESIGNATED CALM WIND RWY. THE WINDS WERE CALM. RWY 21L WAS IN USE. TFC SEEMED TO BE LIGHT. I BELIEVE MOST STUDENT TRAINING ACTIVITY USES RWY 21R. ON MY ARR IN PRESCOTT THE PREVIOUS DAY, I HAD BEEN CLRED TO TAXI TO THE TRANSIENT AREA WITH NO MENTION OF THE INTERSECTING RWY 12. ON A CALM, LIGHT TFC DAY, I CANNOT IMAGINE WHY RWY 12 SHOULD BE IN USE AT ALL. I SEE NO USE FOR RWY 12 EXCEPT WHEN NEEDED BECAUSE OF HIGH XWINDS ON RWY 21L. THE NUMBERING OF RWYS 21 AND 12 IS ITSELF CONFUSING. IT IS EASY TO MISTAKE A TRANSPOSITION OF THE 2 DIGITS. IN TUCSON, MY HOME BASE, THE SAME SIT HAS BEEN RECTIFIED BY RENUMBERING WHAT SHOULD ACTUALLY BE RWY 12L AS RWY 11L. THE HEADING IS REALLY 123 DEGS. I SUGGEST THAT PRESCOTT SHOULD RENUMBER RWY 12 AS RWY 11 INSTEAD, TO REDUCE POSSIBLE CONFUSION. ONCE GND HAD SEEN THAT I WAS EXPERIENCING DIFFICULTY WITH ONE TXWY/RWY SIT, I THINK THEY COULD HAVE BEEN MUCH MORE HELPFUL IN GUIDING ME IN TAXIING RWY 12, WITH ADVICE BEFORE I REACHED THE HOLD SHORT LINE, NOT WAITING UNTIL AFTER A VIOLATION. IN THE FUTURE, I SHALL BE EXTREMELY CAREFUL ABOUT UNDERSTANDING CLRNCS, ESPECIALLY IN UNFAMILIAR SITS.

Data retrieved from NASA's ASRS site as of July 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.