Narrative:

On the date and time described above, my student and I inadvertently entered class B airspace without clearance. We made flight into williams gateway airport on an IFR flight plan uneventfully and opted to depart visually for the return flight. Prior to departing williams gateway, I questioned my student about the class B airspace boundaries and he stated that the floor did not begin until 6000 ft in our area. We decided that leveling off at 5000 ft would be a good plan in order to request our clearance. Having flown into the area on numerous occasions, I knew or I assumed I knew that 6000 ft was indeed the floor of the class B airspace. However, I had taken 5 months off from flight instructing and what I did not realize was that the airspace had been redefined. What used to be the floor at 6000 ft had been lowered to 5000 ft. This change occurred approximately 2 months prior to my return. Thankfully, there were no adverse results from our transgression, other than being chastised by ATC. I believe that contributing factors to this incident were complacency on my part for assuming the airspace boundaries had not changed during my hiatus, and my failure to supervise my student more closely. As my student was checking his VFR sectional, I should have been checking it with him!

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Original NASA ASRS Text

Title: BE76 FLT INSTRUCTOR DOES NOT FOLLOW UP ON INFO PROVIDED BY STUDENT WHEN DEPARTING IWA ARPT AND CLBS INTO PHX CLASS B AIRSPACE PRIOR TO REQUESTING CLASS B ENTRY CLRNC.

Narrative: ON THE DATE AND TIME DESCRIBED ABOVE, MY STUDENT AND I INADVERTENTLY ENTERED CLASS B AIRSPACE WITHOUT CLRNC. WE MADE FLT INTO WILLIAMS GATEWAY ARPT ON AN IFR FLT PLAN UNEVENTFULLY AND OPTED TO DEPART VISUALLY FOR THE RETURN FLT. PRIOR TO DEPARTING WILLIAMS GATEWAY, I QUESTIONED MY STUDENT ABOUT THE CLASS B AIRSPACE BOUNDARIES AND HE STATED THAT THE FLOOR DID NOT BEGIN UNTIL 6000 FT IN OUR AREA. WE DECIDED THAT LEVELING OFF AT 5000 FT WOULD BE A GOOD PLAN IN ORDER TO REQUEST OUR CLRNC. HAVING FLOWN INTO THE AREA ON NUMEROUS OCCASIONS, I KNEW OR I ASSUMED I KNEW THAT 6000 FT WAS INDEED THE FLOOR OF THE CLASS B AIRSPACE. HOWEVER, I HAD TAKEN 5 MONTHS OFF FROM FLT INSTRUCTING AND WHAT I DID NOT REALIZE WAS THAT THE AIRSPACE HAD BEEN REDEFINED. WHAT USED TO BE THE FLOOR AT 6000 FT HAD BEEN LOWERED TO 5000 FT. THIS CHANGE OCCURRED APPROX 2 MONTHS PRIOR TO MY RETURN. THANKFULLY, THERE WERE NO ADVERSE RESULTS FROM OUR TRANSGRESSION, OTHER THAN BEING CHASTISED BY ATC. I BELIEVE THAT CONTRIBUTING FACTORS TO THIS INCIDENT WERE COMPLACENCY ON MY PART FOR ASSUMING THE AIRSPACE BOUNDARIES HAD NOT CHANGED DURING MY HIATUS, AND MY FAILURE TO SUPERVISE MY STUDENT MORE CLOSELY. AS MY STUDENT WAS CHKING HIS VFR SECTIONAL, I SHOULD HAVE BEEN CHKING IT WITH HIM!

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.