A PA28 PLT AND INSTRUCTOR DEPARTED AN ARPT VMC BUT ENTERED IMC PRIOR TO RECEIVING AN IFR CLRNC. LATER IN THE FLT; THEY DETERMINED COM #1 WAS WEAK.

Narrative

FILED AN IFR FLT PLAN THROUGH PHONE. PROCEEDED TO TAXI AND HOLD SHORT OF ACTIVE RWY. CFII TRIED TO ESTABLISH COMS WITH GREAT FALLS FSS AND BILLINGS APCH. UNABLE TO ESTABLISH COMS WITH EITHER FACILITY. AFTER TKOF; WE CONTACTED APCH APPROX 500 FT AGL ASKING FOR OUR CLRNC. APCH INSTRUCTED US TO STAND BY. BOTH THE PLT AND CFII BELIEVED THAT APCH WAS GETTING OUR CLRNC. AFTER WAITING WE ENTERED IFR CONDITIONS. THE CFII THEN CONTACTED APCH AGAIN ASKING FOR OUR CLRNC. APCH THEN INSTRUCTED US TO MAINTAIN VFR. WE REPLIED 'UNABLE.' APCH THEN ASKED IF WE HAD ENTERED IFR CONDITIONS WITHOUT AN IFR CLRNC. WE REPLIED; 'YES WE DID; WE WERE WAITING FOR OUR CLRNC.' ATC REPLIED THAT THEY HAD NOT RECEIVED ANY COMS FROM US. WE THEN RECEIVED OUR CLRNC AND CONTINUED ON OUR RTE. FURTHER INTO THE FLT WHILE IN CONTACT WITH CTR; WE WERE EXPERIENCING SOME DIFFICULTY WITH OUR RADIOS. AFTER SWITCHING FROM COM #1 TO COM #2; CTR ADVISED THAT THEY COULD HEAR US MUCH BETTER. FACTORS: DECREASING CEILINGS. PLT HAVING NO ACTUAL IFR EXPERIENCE. RADIO MISCOM. POSSIBLE RADIO PROBS. POOR JUDGEMENT OF BOTH PLT AND CFII TO ENTER IFR CONDITIONS WITHOUT AN IFR CLRNC.