AA5 PLT OFF SQL BECAME CONFUSED WITH CTLR'S TERMINOLOGY AS TO WHETHER A CLRNC WAS RECEIVED TO ENTER CLASS B AIRSPACE.

Narrative

I DEPARTED SQL WITH 3 PAX; 2 OF THEM CERTIFIED PLTS AS WELL. I IMMEDIATELY CONTACTED NORCAL APCH AND REQUESTED FLT FOLLOWING TO OUR DEST. MY PLAN HAD BEEN TO REMAIN CLR OF THE SFO CLASS B AIRSPACE. HOWEVER; SHORTLY AFTER ACKNOWLEDGING RADAR CONTACT; THE INITIAL CTLR (CTLR A) SAID 'VFR CLB APPROVED; REMAIN AT OR BELOW 3500 FT.' (THE PRECISE WORDS MAY HAVE DIFFERED SLIGHTLY; BUT NOT MUCH.) AT THIS POINT I WAS IN AN AREA WHERE THE CLASS B FLOOR WAS 2500 FT; AND I WAS UNCLR AS TO WHETHER THE CLRNC I HAD JUST RECEIVED CONSTITUTED PERMISSION TO ENTER THE CLASS B OR NOT. I QUERIED MY FELLOW PLT-PAX WHO ALSO THOUGHT IT UNCLR; SO BEFORE CLBING THROUGH 2500 FT I CALLED THE CTLR BACK AND SAID; 'CONFIRM I AM CLRED TO CLB IN CLASS B AIRSPACE?' HE SAID; 'THAT'S RIGHT; GRUMMAN XXXX IS CLRED TO ENTER THE SAN FRANCISCO CLASS B; REMAIN AT OR BELOW 3500 FT.' I WAS GLAD TO HAVE CLARIFIED THINGS; BUT ALSO LEFT WITH THE IMPRESSION THAT HIS PREVIOUS CLRNC HAD IMPLICITLY CLRED ME INTO THE CLASS B AIRSPACE AND THAT MY SUBSEQUENT CALL HAD BEEN UNNECESSARY. A SHORT TIME LATER; I WAS HANDED OFF TO THE NEXT CTLR ON A NEW FREQ; WHO PROCEEDED TO GIVE ME A TURN AND VECTORED ME STRAIGHT OUT OF CLASS B AIRSPACE. UPON EXITING I GOT THE STANDARD 'YOU HAVE LEFT CLASS B AIRSPACE; REMAIN CLR OF CLASS B' WARNING. HE THEN CLRED ME TO PROCEED ON COURSE; WHICH I DID. AT THIS POINT I WAS AT 3500 FT; IN AN AREA WHERE THE CLASS B FLOOR IS 4000 FT. A COUPLE OF MINS LATER; THE CTLR CALLED BACK AND SAID 'GRUMMAN XXXX; VFR CLB APPROVED TO 5500 FT.' I WAS NEARING THE NEXT BOUNDARY WHERE THE CLASS B FLOOR WENT UP TO 6000 FT; AND BASED ON MY EXPERIENCE WITH CTLR 'A' A FEW MINS PREVIOUS; BELIEVED THAT I HAD JUST BEEN CLRED TO 'CUT THE CORNER' THROUGH CLASS B AND CLB UP TO 5500 FT. BECAUSE CTLR A'S CLRNC SEEMED TO HAVE CONTAINED IMPLICIT APPROVAL FOR CLASS B ENTRY; I ASSUMED THAT CTLR B'S CLRNC; WHICH WAS VIRTUALLY IDENTICAL EXCEPT FOR THE ALTS INVOLVED; ALSO INCLUDED SUCH IMPLICIT CLRNC. I BEGAN CLBING; WELL AWARE THAT I WAS STILL (BARELY) IN THE AREA WHERE THE CLASS B FLOOR IS 4000 FT. AS I REACHED THE 20 MI BOUNDARY; WHERE THE CLASS B FLOOR RISES TO 6000 FT; I WAS AT 4800 FT. AT THIS POINT THE CTLR CALLED AND ADVSIED ME THAT I HAD BUSTED THE CLASS B AIRSPACE AND THAT HE HAD NOT CLRED ME TO ENTER IT; BUT THAT I HAD JUST LEFT CLASS B AGAIN. I APOLOGIZED AND SAID I HAD ERRONEOUSLY IMPLIED FROM HIS CLB CLRNC THAT I COULD CLB THROUGH CLASS B AIRSPACE. CLRLY I HAVE LEARNED A LESSON: I WILL NOT ENTER CLASS B AIRSPACE IN THE FUTURE WITHOUT A SPECIFIC CLRNC TO ENTER. I KNEW SUCH A CLRNC WAS REQUIRED; BUT BELIEVED THAT THE CTLR WAS IMPLYING CLRNC JUST AS THE PREVIOUS CTLR HAD APPARENTLY DONE; AND THOUGHT THE CTLRS WERE JUST BEING A BIT SLOPPY. THIS MAY HAVE BEEN THE CASE WITH THE FIRST CTLR; BUT OBVIOUSLY NOT WITH THE SECOND. IN ANY CASE; IN THE FUTURE; I WILL MAKE SURE THAT AN ENTRY CLRNC IS INDISPUTABLE. HOWEVER; I THINK THAT GIVING CLB CLRNCS TO VFR ACFT FLYING UNDER A CLASS B FLOOR; WHERE THE ALT CLRED TO IS ABOVE THE FLOOR; SHOULD BE MORE EXPLICIT TO AVOID SUCH CONFUSION. IT WOULD HAVE BEEN UNDENIABLY CLR IF THE CTLR HAD SAID 'CLB APPROVED TO 5500 FT; REMAIN CLR OF CLASS B;' OR IF HE HAD WITHHELD THE CLB CLRNC UNTIL I WAS UNDER THE 6000 FT FLOOR. OR; HE COULD SIMPLY HAVE SAID; 'CANCEL ALT RESTR' WHICH WOULD HAVE LET ME KNOW THAT I COULD CHOOSE MY ALT; BUT WOULD NOT HAVE SEEMED TO IMPLY CLASS B ENTRY CLRNC. SINCE IT IS CRITICAL FOR SAFETY THAT CTLRS AND PLTS SHARE AN UNDERSTANDING OF WHAT IS MEANT BY CLRNCS GIVEN; SO THAT PLTS GO WHERE THEY ARE EXPECTED TO GO; A LITTLE MORE CONSISTENCY AND LESS AMBIGUITY ON THE PART OF ATC INSTRUCTIONS WOULD GO A LONG WAY TOWARD ENSURING THAT PLTS AND CTLRS SHARE THAT SAME UNDERSTANDING. MY 2 PLT-PAX WERE COMPLETELY IN AGREEMENT; WHEN THIS OCCURRED; THAT THE CLRNC HAD BEEN UNCLR; AND BOTH THOUGHT (AS I DID) THAT I HAD BEEN CLRED TO CLB THROUGH CLASS B AIRSPACE.