PLT FLEW NON ANTI-ICE ACFT INTO KNOWN ICING CONDITIONS. FAULTS AWOS-ASOS FOR NOT BEING CURRENT.

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MINE WAS AN ICING ENCOUNTER THAT MAY HAVE ENDED IN TRAGEDY. THE MAJOR REASON I CHOSE TO LAUNCH WAS THAT I THOUGHT ICING RPTS REFERRED TO TOTAL ACCUMULATION RATHER THAN RATE OF ACCUMULATION. I FIGURED THAT ANY AIRPLANE COULD HANDLE A TRACE OF ICE; OR A LIGHT AMOUNT OF ICE OR EVEN A MODERATE (MODEST?) ICE AMOUNT. THE AIM SPEAKS OF ICE IN TERMS OF RATE OF ACCUMULATION. EVEN TRACE RATE CAN BRING DOWN AN ACFT IN DUE TIME. ON THE DAY OF MY ENCOUNTER WITH ICE; THE FORECAST CALLED FOR MODERATE ICING AND THE PIREPS WERE THE SAME. ONCE AIRBORNE I DID ENCOUNTER MODERATE ICING. BY THE TIME I WAS ON FINAL APCH; 8 MI FROM THE RWY I WAS JUST 300 FT AGL AND UNABLE TO CLB. AN UPDRAFT ASSISTED ME TO MUCH SAFER 800 FT AGL. ON 1 1/2 MI FINAL; MY LOC AND GS QUIT; FLAGGED VICTIMS OF ANTENNA ICING. THE CTLR GAVE ME DEV INFO TO AUGMENT THE ERRATIC; WEAK COCKPIT INDICATIONS. AT 1/2 MI FINAL MY NAV RALLIED BUT THE RWY WAS OBSCURED. HAD TO CROSS THRESHOLD AT ZERO/ZERO. GOOD LNDG. I SUGGEST THE PHRASES TRACE RATE; LIGHT RATE; MODERATE RATE; SEVERE RATE; BE ADOPTED. I CAUTION PEOPLE TO CONSIDER THE LIMITATIONS OF AWOS/ASOS. MY RWY WAS RPTED 300 FT AND 5800 FT RVR; BUT WAS IN FACT AT THRESHOLD: ZERO/ZERO. I WOULD STRONGLY ADVISE PEOPLE WHO FLY THE FRONT RANGE OF THE ROCKIES TO RAISE THEIR PERSONAL ILS MINIMUMS TO 400 AND 1/2 JUST TO COVER AWOS/ASOS BLIND SPOTS. SOME THINGS I DID RIGHT: KEEP MY SPD UP; TOLD ATC ALL PERTINENT DETAILS; FLEW THE AIRPLANE. I SUGGEST THAT THE PHRASE 'KNOWN ICE' BE ADDED TO ALL STANDARD BRIEFINGS.