Narrative:

Prior to take off from cps, I was advised to make a left turn out after takeoff. I complied with these instructions and contacted st louis departure at 1500 ft MSL to request vectors in order to fly to my destination northwest of st louis. My intended route was to fly around the eastern edge of the st louis class B airspace and I was given instructions to make a right turn on a heading that would accomplish this. At this point I was at 1800 ft MSL and 5-8 NM west of cps, slightly west of the st louis arch. (I was also assigned a squawk code at this time.) my intent was, after coming out from under the portion of class B airspace with a floor of 2000 ft MSL, climb to 2000 ft MSL, 1000 ft below the 3000 ft floor of class B at the next stage. After crossing the river immediately north of the st louis arch (my check point for the change in airspace floors) I climbed to 2000 ft MSL. I was then informed that I needed to descend to below 2000 ft in order to stay out of class B airspace. At this point I believed I was clear of class B, but complied by descending to 1800 ft MSL, as low as I felt comfortable considering ground obstructions, I continued along the east side of the mississippi river on vectors supplied by ATC, maintaining 1800 ft MSL. Roughly 8-10 NM northwest of nichols private airport ATC again made reference to staying below 2000 ft MSL to clear class B airspace and that I was roughly at that altitude. The vectors provided to me took me 5 mi west of st louis regional (aln) and then northwest, out of st louis class B airspace. At that time I proceeded on heading to my destination of ffl. To my knowledge at no time did I made an unauthorized entrance into class B airspace. My only possible error was flying too close to the class B, but considering the ground obstacles, there was little choice.

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Original NASA ASRS Text

Title: A PA28 PVT PLT ENTERS THE CLASS B OF STL TWICE WHILE ATTEMPTING TO CIRCUMNAV THE EASTERN INNER RING TOO CLOSELY E OF STL, MO.

Narrative: PRIOR TO TAKE OFF FROM CPS, I WAS ADVISED TO MAKE A L TURN OUT AFTER TKOF. I COMPLIED WITH THESE INSTRUCTIONS AND CONTACTED ST LOUIS DEP AT 1500 FT MSL TO REQUEST VECTORS IN ORDER TO FLY TO MY DEST NW OF ST LOUIS. MY INTENDED RTE WAS TO FLY AROUND THE EASTERN EDGE OF THE ST LOUIS CLASS B AIRSPACE AND I WAS GIVEN INSTRUCTIONS TO MAKE A R TURN ON A HEADING THAT WOULD ACCOMPLISH THIS. AT THIS POINT I WAS AT 1800 FT MSL AND 5-8 NM W OF CPS, SLIGHTLY W OF THE ST LOUIS ARCH. (I WAS ALSO ASSIGNED A SQUAWK CODE AT THIS TIME.) MY INTENT WAS, AFTER COMING OUT FROM UNDER THE PORTION OF CLASS B AIRSPACE WITH A FLOOR OF 2000 FT MSL, CLB TO 2000 FT MSL, 1000 FT BELOW THE 3000 FT FLOOR OF CLASS B AT THE NEXT STAGE. AFTER XING THE RIVER IMMEDIATELY N OF THE ST LOUIS ARCH (MY CHK POINT FOR THE CHANGE IN AIRSPACE FLOORS) I CLBED TO 2000 FT MSL. I WAS THEN INFORMED THAT I NEEDED TO DSND TO BELOW 2000 FT IN ORDER TO STAY OUT OF CLASS B AIRSPACE. AT THIS POINT I BELIEVED I WAS CLR OF CLASS B, BUT COMPLIED BY DSNDING TO 1800 FT MSL, AS LOW AS I FELT COMFORTABLE CONSIDERING GND OBSTRUCTIONS, I CONTINUED ALONG THE E SIDE OF THE MISSISSIPPI RIVER ON VECTORS SUPPLIED BY ATC, MAINTAINING 1800 FT MSL. ROUGHLY 8-10 NM NW OF NICHOLS PVT ARPT ATC AGAIN MADE REF TO STAYING BELOW 2000 FT MSL TO CLR CLASS B AIRSPACE AND THAT I WAS ROUGHLY AT THAT ALT. THE VECTORS PROVIDED TO ME TOOK ME 5 MI W OF ST LOUIS REGIONAL (ALN) AND THEN NW, OUT OF ST LOUIS CLASS B AIRSPACE. AT THAT TIME I PROCEEDED ON HEADING TO MY DEST OF FFL. TO MY KNOWLEDGE AT NO TIME DID I MADE AN UNAUTH ENTRANCE INTO CLASS B AIRSPACE. MY ONLY POSSIBLE ERROR WAS FLYING TOO CLOSE TO THE CLASS B, BUT CONSIDERING THE GND OBSTACLES, THERE WAS LITTLE CHOICE.

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.