Narrative:

We had pushed back from the gate (on the end of the concourse) and the taxi clearance was 'right turn on 'P' to runway 15R.' coming out of the alleyway I thought that 'P' would be the second right turn, 'a' being the first. I got this from looking at the 10-9 page. It turns out 'a' is the ramp, so 'P' is the first right turn, and '4/22' is the second right. I stopped the aircraft prior to taxiing onto the runway, then got permission from ground to use it for taxi. I was able to tell it was a runway because I had good visibility and could see the distance remaining markers. Had it been dark or foggy I would not have noticed it was a runway. Suggested corrective actions: more paint on the ground showing txwys and hold short points. The entire width of every runway entry point should be painted as the red box with the runway name in it. (This particular entry point is very wide with the red box only printed on the north end). Also, if there had been 'a' and 'P' painted boxed on the ground, I would never have gotten close to the runway in the first place. More paint, where it is intuitively obvious to the pilot, is a low tech solution to a very real problem, and not just at bwi, but everywhere.

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Original NASA ASRS Text

Title: ACR STOPS SHORT OF RWY TO REQUEST NEW TAXI CLRNC WHEN IT BECOMES APPARENT THAT ORIGINAL CLRNC WAS NOT FOLLOWED DUE TO CONFUSION WITH ARPT DIAGRAM AND SURFACE MARKINGS.

Narrative: WE HAD PUSHED BACK FROM THE GATE (ON THE END OF THE CONCOURSE) AND THE TAXI CLRNC WAS 'R TURN ON 'P' TO RWY 15R.' COMING OUT OF THE ALLEYWAY I THOUGHT THAT 'P' WOULD BE THE SECOND R TURN, 'A' BEING THE FIRST. I GOT THIS FROM LOOKING AT THE 10-9 PAGE. IT TURNS OUT 'A' IS THE RAMP, SO 'P' IS THE FIRST R TURN, AND '4/22' IS THE SECOND R. I STOPPED THE ACFT PRIOR TO TAXIING ONTO THE RWY, THEN GOT PERMISSION FROM GND TO USE IT FOR TAXI. I WAS ABLE TO TELL IT WAS A RWY BECAUSE I HAD GOOD VISIBILITY AND COULD SEE THE DISTANCE REMAINING MARKERS. HAD IT BEEN DARK OR FOGGY I WOULD NOT HAVE NOTICED IT WAS A RWY. SUGGESTED CORRECTIVE ACTIONS: MORE PAINT ON THE GND SHOWING TXWYS AND HOLD SHORT POINTS. THE ENTIRE WIDTH OF EVERY RWY ENTRY POINT SHOULD BE PAINTED AS THE RED BOX WITH THE RWY NAME IN IT. (THIS PARTICULAR ENTRY POINT IS VERY WIDE WITH THE RED BOX ONLY PRINTED ON THE N END). ALSO, IF THERE HAD BEEN 'A' AND 'P' PAINTED BOXED ON THE GND, I WOULD NEVER HAVE GOTTEN CLOSE TO THE RWY IN THE FIRST PLACE. MORE PAINT, WHERE IT IS INTUITIVELY OBVIOUS TO THE PLT, IS A LOW TECH SOLUTION TO A VERY REAL PROB, AND NOT JUST AT BWI, BUT EVERYWHERE.

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.