Narrative:

We departed ilg, a class D satellite airport. Our course to ttn went through the center of phl's class B airspace. After leaving ilg tower frequency, we contacted phl approach control. We were assigned a squawk code and idented. Throughout the initial communications with phl, we continued our climb. When radar contact was made, our indicated altitude was 3000 ft. The floor of the overflying class B airspace was 3000 ft. The controller remarked that we were already in the class B airspace and cleared us to 3500 ft with a vector around phl international airport. I should have stopped our climb well clear of 3000 ft. Fatigue was probably the greatest contributing factor. I am a cfii, the student is post solo/pre cross country solo.

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Original NASA ASRS Text

Title: FLT INSTRUCTOR WITH STUDENT FLYING IN A C152 ENTERED CLASS B AIRSPACE WHILE CLBING OUT VFR FROM AN ARPT UNDERLYING THE EDGE OF THE AIRSPACE.

Narrative: WE DEPARTED ILG, A CLASS D SATELLITE ARPT. OUR COURSE TO TTN WENT THROUGH THE CTR OF PHL'S CLASS B AIRSPACE. AFTER LEAVING ILG TWR FREQ, WE CONTACTED PHL APCH CTL. WE WERE ASSIGNED A SQUAWK CODE AND IDENTED. THROUGHOUT THE INITIAL COMS WITH PHL, WE CONTINUED OUR CLB. WHEN RADAR CONTACT WAS MADE, OUR INDICATED ALT WAS 3000 FT. THE FLOOR OF THE OVERFLYING CLASS B AIRSPACE WAS 3000 FT. THE CTLR REMARKED THAT WE WERE ALREADY IN THE CLASS B AIRSPACE AND CLRED US TO 3500 FT WITH A VECTOR AROUND PHL INTL ARPT. I SHOULD HAVE STOPPED OUR CLB WELL CLR OF 3000 FT. FATIGUE WAS PROBABLY THE GREATEST CONTRIBUTING FACTOR. I AM A CFII, THE STUDENT IS POST SOLO/PRE XCOUNTRY SOLO.

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.