BEECHCRAFT KING AIR 300 PLTS FAILED TO CONTACT TWR AND OBTAIN LNDG CLRNC.

Narrative

AFTER ESTABLISHING ACFT ON ILS FOR RWY 5R AT INDY; FAILED TO CONTACT TWR AT FINAL APCH FIX. PNF WAS ON UNICOM PRIOR TO FAF WHICH WAS A BAD IDEA IN HINDSIGHT BECAUSE IT LED ME TO THE BELIEF THAT COMS WERE BEING HANDLED; HOWEVER; MY SITUATIONAL AWARENESS WAS LOW DUE TO THIS BEING THE THIRD APCH TO LOW MINIMUMS IN THE LAST 1 1/2 HRS; AND MY CONCENTRATION ON THE VERY LOW APCH WE WERE PRESENTLY CONDUCTING. HOWEVER; THIS IS A VERY WEAK EXCUSE FOR PLTS OF OUR EXPERIENCE. I WILL SAY THAT AFTER FLYING THE MAJORITY OF MY CAREER SINGLE PLT; WHICH LNDG WITHOUT A CLRNC NEVER HAPPENED; 2 PLTS IN A CREW LEAD TO THE DEPENDENCE THAT THE OTHER HAS TAKEN CARE OF THINGS; SUCH AS LNDG CLRNCS OR RPTING BASE LEGS TO TWRS; ETC. ONE OTHER POSSIBLE CONTRIBUTING FACTOR IS THAT WHEN THE FINAL CTLR CLRS YOU FOR AN APCH WHEN THE WX IS SO BAD YOUR THINKING ALTERNATES ON MISSED APCH; YOU KNOW THE TWR CAN'T EVEN SEE YOU WHEN YOU LAND; THE PHRASE 'CLRED FOR THE APCH' GIVES A MINDSET THAT IT'S YOUR SHOW AND YOU'RE CLRED ALL THE WAY TO THE GND.