PLT OF AN ATX SMA SEL FLEW INTO THE GND DURING A VFR APCH TO AN UNCTLED ARPT.

Narrative

TOOK OFF FROM BARROW ARPT UNDER VFR CONDITIONS. CEILING WAS 1500 FT. CRUISED TO ATQUSAK AT 1000 FT. ENTERED TFC PATTERN AT 900 FT MSL (ARPT ELEVATION 95 FT) AND PROCEEDED ON AN EXTENDED DOWNWIND. (AS I PASSED OVER THE RWY 06-24; I NOTICED A FOG BANK 1/4 MI TO THE N). TURNING BASE TO FINAL I COULD SEE THAT MY HORIZ VISIBILITY WAS GOING. (AT THE TIME IT WAS PROBABLY 1-3 MI). I CONTINUED ON AND ENCOUNTERED FREEZING DRIZZLE THAT COVERED THE WINDSHIELD. I LOOKED DOWN OUT THE SIDE WINDOW TO GET SOME SORT OF VERT REF; THEN BACK OUT THE WINDSCREEN AND THEN MY INSTS. JUST AS I NOTICED THAT I HAD LET MY ALT SLIP DOWN TO 150 FT (USUALLY WHAT ALTIMETER INDICATES WHEN ON RWY). I IMPACTED WITH THE GND. THE ACFT SLID ABOUT 200 YARDS ON A FROZEN LAKE WHERE IT CAME TO REST ON ITS NOSE. ONLY 1 PAX WAS ON BOARD AND 800 LBS OF FREIGHT. NEITHER OF US SUSTAINED ANY TYPE OF INJURY WHATSOEVER. PREVAILING VISIBILITY AT TIME OF IMPACT WAS PROBABLY AN ESTIMATED 1/4 MI. THE MAIN FACTORS CONTRIBUTING TO THIS ACCIDENT WERE: THE EVER PRESENT WHITE OUT CONDITIONS THAT EXIST UP HERE BECAUSE OF LACK OF DARK OBJECTS TO CONTRAST WITH SNOW. FAILURE TO COMMENCE AN IMMEDIATE 'GAR' WHEN WINDSCREEN ICED OVER. THE ATTEMPT TO 'GET UNDER' THE OBSCURATION WHEN I WAS LOW IN THE FIRST PLACE. THE CONTINUATION IN ESSENTIALLY IFR CONDITIONS WITH ONLY VERT VISIBILITY. PLT EGO. COULD HAVE EASILY AVOID INCIDENT BY GIVING MYSELF A VISIBILITY AND ALT MINIMUM.