Narrative:

Flight from fdk to blm, using GPS direct. Strictly VFR day conditions. Radar contact with bwi, handed off to ZNY. Handed off to phl approach, contacted them with assigned squawk, but was told I could not be accommodated due to traffic. Was then in cruise descent over phl. I requested the next sector, and was told I could contact mcguire in 5 mi. Mcguire advised radar was OTS. I confirmed they had lost both primary and secondary. By now I had cleared the class B airspace to the east, but was at 6500 ft and descending. It is possible I inadvertently caught the upper corner of phl class B in the descent. I should have set the altitude preselect to say 7500 ft, as a reminder to confirm further descent would be clear the phl class B airspace.

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Original NASA ASRS Text

Title: PA46 ENRTE TO BLM HAD BEEN ADVISED BY PHL APCH CTL THEY COULD NOT CLR THEM THROUGH THEIR CLASS B AIRSPACE. RPTR HAD CONTACTED MCGUIRE BUT WAS TOLD THEIR RADAR OTS. HAD BEGUN DSCNT AND PRIOR TO CLRING THE CLASS B AIRSPACE PHL, DSNDED TO 6500 FT PENETRATING THE CLASS B BY 500 FT.

Narrative: FLT FROM FDK TO BLM, USING GPS DIRECT. STRICTLY VFR DAY CONDITIONS. RADAR CONTACT WITH BWI, HANDED OFF TO ZNY. HANDED OFF TO PHL APCH, CONTACTED THEM WITH ASSIGNED SQUAWK, BUT WAS TOLD I COULD NOT BE ACCOMMODATED DUE TO TFC. WAS THEN IN CRUISE DSCNT OVER PHL. I REQUESTED THE NEXT SECTOR, AND WAS TOLD I COULD CONTACT MCGUIRE IN 5 MI. MCGUIRE ADVISED RADAR WAS OTS. I CONFIRMED THEY HAD LOST BOTH PRIMARY AND SECONDARY. BY NOW I HAD CLRED THE CLASS B AIRSPACE TO THE E, BUT WAS AT 6500 FT AND DSNDING. IT IS POSSIBLE I INADVERTENTLY CAUGHT THE UPPER CORNER OF PHL CLASS B IN THE DSCNT. I SHOULD HAVE SET THE ALT PRESELECT TO SAY 7500 FT, AS A REMINDER TO CONFIRM FURTHER DSCNT WOULD BE CLR THE PHL CLASS B AIRSPACE.

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.