Narrative:

Routine IFR flight. Had just flown to bis to pick up passenger. Did not encounter icing on flight up to bis, so filed same altitude for return. Clearance, departure and communications were routine. Leveled at 5000' MSL after departure and set up cruise. Reported level and was acknowledged by controller. After about 5 mins, small amount of ice began to accumulate. After approximately 10 mins it was approximately 1/8-1/4', so attempted contact with departure to request altitude change. After repeated attempts were unsuccessful, and total of approximately 3/8-1/2' ice had formed, squawked 7700 for 1 min, then 7600. IFR descent was made to VMC at 4400' MSL. Continued VFR descent to 3500', VFR cruising altitude. Ice melted within 10 mins, but still unable to contact ATC on all appropriate frequencys. Normal flight in VMC with calls attempted every 3-5 mins. Continued squawking 7600' for 15 mins, 7700 FPM per procedures. Destination airport sighted at 25 mi, radio calls unanswered. Finally able to contact FSS at 20 mi out. Normal VFR descent and landing made. Was informed through FSS that ATC appreciated proper procedures for NORDO were carried out. Unable to locate cause of NORDO condition. Suspect possible icing on antenna, though all navigation radios functioned normally.

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Original NASA ASRS Text

Title: GA SMA LOST RADIO COM AT CRUISE ALT BETWEEN BIS AND ABR. USED LOST COM PROC AND CONTINUED VFR TO ABR.

Narrative: ROUTINE IFR FLT. HAD JUST FLOWN TO BIS TO PICK UP PAX. DID NOT ENCOUNTER ICING ON FLT UP TO BIS, SO FILED SAME ALT FOR RETURN. CLRNC, DEP AND COMS WERE ROUTINE. LEVELED AT 5000' MSL AFTER DEP AND SET UP CRUISE. RPTED LEVEL AND WAS ACKNOWLEDGED BY CTLR. AFTER ABOUT 5 MINS, SMALL AMOUNT OF ICE BEGAN TO ACCUMULATE. AFTER APPROX 10 MINS IT WAS APPROX 1/8-1/4', SO ATTEMPTED CONTACT WITH DEP TO REQUEST ALT CHANGE. AFTER REPEATED ATTEMPTS WERE UNSUCCESSFUL, AND TOTAL OF APPROX 3/8-1/2' ICE HAD FORMED, SQUAWKED 7700 FOR 1 MIN, THEN 7600. IFR DSCNT WAS MADE TO VMC AT 4400' MSL. CONTINUED VFR DSCNT TO 3500', VFR CRUISING ALT. ICE MELTED WITHIN 10 MINS, BUT STILL UNABLE TO CONTACT ATC ON ALL APPROPRIATE FREQS. NORMAL FLT IN VMC WITH CALLS ATTEMPTED EVERY 3-5 MINS. CONTINUED SQUAWKING 7600' FOR 15 MINS, 7700 FPM PER PROCS. DEST ARPT SIGHTED AT 25 MI, RADIO CALLS UNANSWERED. FINALLY ABLE TO CONTACT FSS AT 20 MI OUT. NORMAL VFR DSCNT AND LNDG MADE. WAS INFORMED THROUGH FSS THAT ATC APPRECIATED PROPER PROCS FOR NORDO WERE CARRIED OUT. UNABLE TO LOCATE CAUSE OF NORDO CONDITION. SUSPECT POSSIBLE ICING ON ANTENNA, THOUGH ALL NAV RADIOS FUNCTIONED NORMALLY.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.