Narrative:

Private, non instrument rated, relatively low time. Low experience dealing with ATC. Long wbound cross country returning home, about 4 hours in the air at the time. Flight from XXX, al, to basically parallel to the coast. Had used flight following for the last 2 hours of flight. Used XXX.xx frequency to contact houston approach. Descended to 3500 ft where I could change altitude quicker, if requested. Contacted approach about 25 mi out, due west of downtown. Received identify and requested to transit airspace. Controller asked for destination airport X and additional transmission about maintenance VFR and interstate 10. Part of the transmission was clipped off. As I was over interstate 10, I understood it as a position report. I continued wbound, expecting clearance for the airspace, and receiving TA's. Began to realize I was either at or in the class B airspace when the controller asked if I had interstate 10 in sight. The brain light finally came on. I asked the controller if he wanted me in the VFR corridor to which he responded in the affirmative '...as instructed.' I immediately turned northwest toward the corridor and descended to get below the floor of the class B airspace. 'Maintain VFR' has become a code word for 'stay out of class B airspace.' I guess this wording is chosen to fit the regulations and situation. For VFR pilots, that phrase may not carry the meaning desired. To me, 'maintain VFR' is like saying 'keep flying the airplane.' I know you need clearance to enter, yet the controller did not say 'stay out' which would have been crystal clear. I think a better terminology is needed.

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Original NASA ASRS Text

Title: GA PLT MISSES I90 CLRNC INSTRUCTIONS AND ENTERS CLASS B AIRSPACE WITHOUT AUTH.

Narrative: PVT, NON INST RATED, RELATIVELY LOW TIME. LOW EXPERIENCE DEALING WITH ATC. LONG WBOUND XCOUNTRY RETURNING HOME, ABOUT 4 HRS IN THE AIR AT THE TIME. FLT FROM XXX, AL, TO BASICALLY PARALLEL TO THE COAST. HAD USED FLT FOLLOWING FOR THE LAST 2 HRS OF FLT. USED XXX.XX FREQ TO CONTACT HOUSTON APCH. DSNDED TO 3500 FT WHERE I COULD CHANGE ALT QUICKER, IF REQUESTED. CONTACTED APCH ABOUT 25 MI OUT, DUE W OF DOWNTOWN. RECEIVED IDENT AND REQUESTED TO TRANSIT AIRSPACE. CTLR ASKED FOR DEST ARPT X AND ADDITIONAL XMISSION ABOUT MAINT VFR AND INTERSTATE 10. PART OF THE XMISSION WAS CLIPPED OFF. AS I WAS OVER INTERSTATE 10, I UNDERSTOOD IT AS A POS RPT. I CONTINUED WBOUND, EXPECTING CLRNC FOR THE AIRSPACE, AND RECEIVING TA'S. BEGAN TO REALIZE I WAS EITHER AT OR IN THE CLASS B AIRSPACE WHEN THE CTLR ASKED IF I HAD INTERSTATE 10 IN SIGHT. THE BRAIN LIGHT FINALLY CAME ON. I ASKED THE CTLR IF HE WANTED ME IN THE VFR CORRIDOR TO WHICH HE RESPONDED IN THE AFFIRMATIVE '...AS INSTRUCTED.' I IMMEDIATELY TURNED NW TOWARD THE CORRIDOR AND DSNDED TO GET BELOW THE FLOOR OF THE CLASS B AIRSPACE. 'MAINTAIN VFR' HAS BECOME A CODE WORD FOR 'STAY OUT OF CLASS B AIRSPACE.' I GUESS THIS WORDING IS CHOSEN TO FIT THE REGS AND SIT. FOR VFR PLTS, THAT PHRASE MAY NOT CARRY THE MEANING DESIRED. TO ME, 'MAINTAIN VFR' IS LIKE SAYING 'KEEP FLYING THE AIRPLANE.' I KNOW YOU NEED CLRNC TO ENTER, YET THE CTLR DID NOT SAY 'STAY OUT' WHICH WOULD HAVE BEEN CRYSTAL CLR. I THINK A BETTER TERMINOLOGY IS NEEDED.

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.