Narrative:

At approximately XA00 local, I landed on an offshore platform and shut down. There were isolated rain showers in the area, but the winds were light and I observed no lightning. After about 1 hour, the showers were getting closer, more prevalent, and the winds increasing. I advised the customer we should go. At XB35 local, I took off toward galveston. About 5 mi into the flight, I ran into rain showers. I tried to return to the platform but couldn't, nor could I see the beach (which was visible when I untied the aircraft). I tried to make another platform a fellow pilot had told me was in the clear, but again ran into rain and reduced visibility. Eventually I was unable to maintain VFR and surface reference with the water. I went on instruments, climbed to 1000 ft MSL, contacted houston approach, declared an emergency and asked for vectors to somewhere to get me down. Galveston WX was 9 NM with few scattered at 1100 ft. I descended to 800 ft and flew the assigned heading (010 degrees) toward galveston. At about 5 mi out, I saw the beach and continued to galveston. I remained with approach until I had the field in sight, then closed with approach on landing.

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Original NASA ASRS Text

Title: A HELI PLT IS UNABLE TO MAINTAIN VFR AND DECLARES AN EMER UNTIL VFR AND LANDS AT GLS.

Narrative: AT APPROX XA00 LCL, I LANDED ON AN OFFSHORE PLATFORM AND SHUT DOWN. THERE WERE ISOLATED RAIN SHOWERS IN THE AREA, BUT THE WINDS WERE LIGHT AND I OBSERVED NO LIGHTNING. AFTER ABOUT 1 HR, THE SHOWERS WERE GETTING CLOSER, MORE PREVALENT, AND THE WINDS INCREASING. I ADVISED THE CUSTOMER WE SHOULD GO. AT XB35 LCL, I TOOK OFF TOWARD GALVESTON. ABOUT 5 MI INTO THE FLT, I RAN INTO RAIN SHOWERS. I TRIED TO RETURN TO THE PLATFORM BUT COULDN'T, NOR COULD I SEE THE BEACH (WHICH WAS VISIBLE WHEN I UNTIED THE ACFT). I TRIED TO MAKE ANOTHER PLATFORM A FELLOW PLT HAD TOLD ME WAS IN THE CLR, BUT AGAIN RAN INTO RAIN AND REDUCED VISIBILITY. EVENTUALLY I WAS UNABLE TO MAINTAIN VFR AND SURFACE REF WITH THE WATER. I WENT ON INSTS, CLBED TO 1000 FT MSL, CONTACTED HOUSTON APCH, DECLARED AN EMER AND ASKED FOR VECTORS TO SOMEWHERE TO GET ME DOWN. GALVESTON WX WAS 9 NM WITH FEW SCATTERED AT 1100 FT. I DSNDED TO 800 FT AND FLEW THE ASSIGNED HEADING (010 DEGS) TOWARD GALVESTON. AT ABOUT 5 MI OUT, I SAW THE BEACH AND CONTINUED TO GALVESTON. I REMAINED WITH APCH UNTIL I HAD THE FIELD IN SIGHT, THEN CLOSED WITH APCH ON LNDG.

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.