VERY LARGE HOT AIR BALLOON PENETRATES CLASS 'B' DUE TO UNCTLED WIND DRIFT.

Narrative

I WAS PERFORMING A COMMERCIAL SIGHT-SEEING TOUR IN A 12 PAX HOT AIR BALLOON; APPROX 6 MI NW OF THE MIRAMAR NAS; IN AN ESTABLISHED LAUNCH AREA. FROM THIS SITE; WINDS HDG N TO NE ARE NECESSARY TO FLY AWAY FROM HVY CONGESTION FOR A SAFE LNDG SITE. UPON TKOF (AFTER DETERMINING MY LAUNCH SITE BY CALLING FLT SVC WHO RPTED SURFACE WINDS ALOFT HDG TO THE N AND NE AND OBSERVING THESE CURRENTS ON THE GND FROM TEST HELIUM BALLOONS); I IMMEDIATELY HEADED E; SLIGHTLY SE. IF I CONTINUED IN THIS DIRECTION; I WOULD MOST CERTAINLY FLY THROUGH MIRAMAR'S ATA AND THE TCA IN THE AREA; AND LAND IN A CONGESTED AREA IN A RESIDENTIAL AREA DOWNWIND. THIS IS WHEN I DECIDED IT WOULD BE NECESSARY TO ENTER THE TCA ABOVE THE 1500 FT MSL BASE TO SEARCH FOR A CURRENT HDG TO THE N. THERE WERE ALSO OTHER BALLOONS IN THE AREA WHO RPTED (ON 2-WAY RADIO) THAT AT 3000 FT THERE WAS A CURRENT HDG N. I THEN DECIDED TO ENTER THE TCA THEN; AND HEAD N AS QUICKLY AS POSSIBLE. WE (BALLOONS) DO NOT NORMALLY CARRY XPONDERS; SO I KNEW I WOULD BE REFUSED UPON REQUESTING PERMISSION; SO I ENTERED WITHOUT REQUESTING. THERE WAS NO MIRAMAR JET ACTIVITY AND IT WAS A HIGH CEILING; SO I SAW NO IMMEDIATE DANGER. I BELIEVE THE PROB AROSE FROM THE FACT THAT I JUDGED MY LAUNCH SITE CHOICE LARGELY ON THE PREVIOUS NIGHT'S CONDITIONS; WHEN STRONGER CURRENTS TO THE N WERE PRESENT. IN THIS AREA; WHEN THE WIND IS STRONG (12-15 KTS) AND IS FORECAST TO DIMINISH RAPIDLY NEAR SUNSET; THE DIRECTION CAN VARY DRAMATICALLY. I DID NOT ACCOUNT FOR THIS; AND SHOULD HAVE LAUNCHED FROM A MORE 'FORGIVING' AREA. OF COURSE; CARRYING XPONDERS AND FURTHERING BALLOON AND ATC RELATIONS WOULD HELP THIS TYPE OF PROB AS WELL. ONCE I GOT THE N CURRENTS NECESSARY; I LANDED IN ONE OF THE NORMAL SITES WITH NO FURTHER INCIDENT.