Narrative:

I requested air traffic services from mcguire approach (127.5) who assigned me a squawk code and handed me off to philadelphia approach (123.8). Philadelphia approach instructed me to maintain 4000 ft and proceed on course. The frequency was fairly busy. When I was approximately 12 mi from N10 and 5 NM north of nxx, I requested a discretionary descent into N10. Philadelphia approved descent as requested (maintain VFR), but advised that I had sbound traffic at 12 O'clock position, 3 mi at 3500 ft. I indicated I did not have the traffic in sight, and would prefer to delay my descent until I had passed the traffic. Philadelphia instructed me instead to turn course 180 degrees, vectors for traffic. The 180 degree vector had put me above nxx's class D airspace. Philadelphia approach, frequency 123.8, is also approach control for nxx. Shortly after this, I saw the cessna at 2:30 O'clock position, and slightly below me. I informed philadelphia that I had the traffic. Philadelphia informed me to 'maintain VFR separation with traffic, descend at discretion, proceed on course, and contact philadelphia on 126.85.' I thought philadelphia had cleared me into nxx's (willow grove) class D airspace (top 2900 ft), and was coordinating with the tower. I turned on course and expedited my descent to 2500 ft to insure adequate traffic separation. I continued a gradual descent to 1500 ft. When the frequency was clear, I checked in with philadelphia on 126.85. The new controller informed me that I had not been cleared into nxx class D airspace. When I repeated my clearance, the new controller informed me that other controller also gave me a clearance limit to 'remain clear of class D airspace.' she suggested that maybe I didn't hear it.

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Original NASA ASRS Text

Title: PA28 PLT INBOUND TO NXX MISINTERPRETS APCH CTLR'S INSTRUCTIONS AND DSNDS INTO NXX CLASS D WITHOUT A CLRNC.

Narrative: I REQUESTED AIR TFC SVCS FROM MCGUIRE APCH (127.5) WHO ASSIGNED ME A SQUAWK CODE AND HANDED ME OFF TO PHILADELPHIA APCH (123.8). PHILADELPHIA APCH INSTRUCTED ME TO MAINTAIN 4000 FT AND PROCEED ON COURSE. THE FREQ WAS FAIRLY BUSY. WHEN I WAS APPROX 12 MI FROM N10 AND 5 NM N OF NXX, I REQUESTED A DISCRETIONARY DSCNT INTO N10. PHILADELPHIA APPROVED DSCNT AS REQUESTED (MAINTAIN VFR), BUT ADVISED THAT I HAD SBOUND TFC AT 12 O'CLOCK POS, 3 MI AT 3500 FT. I INDICATED I DID NOT HAVE THE TFC IN SIGHT, AND WOULD PREFER TO DELAY MY DSCNT UNTIL I HAD PASSED THE TFC. PHILADELPHIA INSTRUCTED ME INSTEAD TO TURN COURSE 180 DEGS, VECTORS FOR TFC. THE 180 DEG VECTOR HAD PUT ME ABOVE NXX'S CLASS D AIRSPACE. PHILADELPHIA APCH, FREQ 123.8, IS ALSO APCH CTL FOR NXX. SHORTLY AFTER THIS, I SAW THE CESSNA AT 2:30 O'CLOCK POS, AND SLIGHTLY BELOW ME. I INFORMED PHILADELPHIA THAT I HAD THE TFC. PHILADELPHIA INFORMED ME TO 'MAINTAIN VFR SEPARATION WITH TFC, DSND AT DISCRETION, PROCEED ON COURSE, AND CONTACT PHILADELPHIA ON 126.85.' I THOUGHT PHILADELPHIA HAD CLRED ME INTO NXX'S (WILLOW GROVE) CLASS D AIRSPACE (TOP 2900 FT), AND WAS COORDINATING WITH THE TWR. I TURNED ON COURSE AND EXPEDITED MY DSCNT TO 2500 FT TO INSURE ADEQUATE TFC SEPARATION. I CONTINUED A GRADUAL DSCNT TO 1500 FT. WHEN THE FREQ WAS CLR, I CHKED IN WITH PHILADELPHIA ON 126.85. THE NEW CTLR INFORMED ME THAT I HAD NOT BEEN CLRED INTO NXX CLASS D AIRSPACE. WHEN I REPEATED MY CLRNC, THE NEW CTLR INFORMED ME THAT OTHER CTLR ALSO GAVE ME A CLRNC LIMIT TO 'REMAIN CLR OF CLASS D AIRSPACE.' SHE SUGGESTED THAT MAYBE I DIDN'T HEAR IT.

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.