B200 ACFT ON ILS APCH IN IMC TO UNCTLED ARPT HEARS BONANZA ACFT DEPARTING ON OPPOSITE RWY WITHOUT A FLT PLAN INTO IMC WX. RPTR PLT DSNDED BELOW GLIDE PATH TO BREAK OUT IN ORDER TO LOCATE INTRUDER ACFT AND PASSES VERY CLOSE.

Narrative

SINGLE PLT AIR TAXI CHARTER INTO STC (CLASS E AIRSPACE) WITH 8 PAX ONBOARD A BE B200. WX CONDITIONS RPTED WERE 500 FT OVCST WITH 5 MI VISIBILITY. MSP CTR CLRED ME FOR THE ILS TO RWY 31. DURING THE DSCNT OUTSIDE THE MARKER I HEARD A BONANZA TRYING TO REACH CTR ON THE GND FOR AN IFR CLRNC OFF TO MOT. XMITTING ON CTAF I RPTED MY POS MANY TIMES AND ALSO XMITTED ON CTR MARKER INBOUND SO THE BONANZA MAY GET A HINT. THE BONANZA THEN SAID THAT HE WAS DEPARTING RWY 31. I RPTED MY POS INBOUND AND ASKED HIM IF HE KNEW THE FIELD WAS IFR. HE CALLS BACK ON CTAF THAT HE IS ACTUALLY DEPARTING RWY 13. I CALLED HIM BACK AGAIN TO LET HIM KNOW THAT I WAS ON THE APCH TO RWY 31 AND IF HE KNEW HE WAS COMING DIRECTLY AT ME. NO REPLY. I CALLED CTR AND SAID A BONANZA HAD CALLED OFF OF RWY 13. CTR SAID THAT HE DOES NOT HAVE CLRNC. I XMITTED ON CTAF AGAIN NOW WITHIN 3 MI. NO REPLY. I FLEW THE GS LOW SO I COULD GET INTO VMC SOONER TO SEE WHERE THIS GUY IS AND BROKE OUT OF THE OVCST ABOUT 500 FT. AT ABOUT 100-200 FT BELOW THE OVCST AND WITHIN 2 MI FINAL A BONANZA GOES OVER THE TOP OF ME INTO THE CLOUDS. HE HAD DEPARTED RWY 13 STRAIGHT OUT AND INTO THE CLOUDS. HE WOULD NOT ACKNOWLEDGE ME BUT THEN CALLED UNICOM BACK TO GIVE A TOPS RPT. I FEEL THAT IF I WOULD NOT HAVE FOLLOWED THE GS LOW TO GET INTO VMC AND GET VISUAL ON THE BONANZA; IT COULD HAVE BEEN AN APCH INTO A V-TAILED BONANZA. THAT V-TAILED BONANZA JEOPARDIZED ALL THE LIVES IN BOTH PLANES -- BAD BONANZA PLT.