Narrative:

I realized I had a radio failure as I was handed off from charleston approach to ZID. I could receive, however, I could not transmit -- carrier no voice. Approximately 10 mins beforehand, I was getting a high-pitched hum over all my headsets and aircraft speaker that had increased in intensity to annoying proportions. I was at the point of handoff passing overhead an airport. I did not want to continue the flight. I could still hear ZID. Being overtop this airport, my thought was to proceed VFR, land quickly and to call in. I did not squawk 7700/7600 immediately because, in 1 min I would have been out of radar coverage either on the ground or close to landing and all ATC might've seen is the emergency code 7700 and then I drop out of sight. In retrospect, I was out-thinking the controllers. As I banked toward the airport in question, descending, I could now make out that this airport had not yet opened. There were no facilities and no visible X's on the runway, and I would not be able to call anyone. At precisely this moment, ZID asked me if I was going back to crw to identify. I figured at that point that was the right thing to do. I responded and he cleared me to crw at 4000. Also, at this point, being aware of having left my original altitude to make a VFR descent and landing I had better squawk 7700/7600, but at precisely this moment, ZID asked if I had an emergency. I did not identify, responding in the negative. So, at that point it seemed contradictory to then squawk 7700, and with 1-WAY radio communication possible, coupled with my ability to reply by transponder and my proximity to charleston, I decided not to change my code. From this point from the time I first realized my radio failure it was approximately 2 mins. This all happened very quickly. There was no confusion that followed. I was easily handed back to charleston approach without a traffic conflict. Traffic around charleston was light and I easily landed without incident or difficulty. I was then asked to call the tower. I did so and talked to the supervisor. He made it clear that it would've been easier for them if I had squawked 7700/7600 immediately before leaving my altitude.

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Original NASA ASRS Text

Title: PLT OF SMA ACFT DEVIATED FROM ASSIGNED ALT DUE THE ACFT COM RADIO MALFUNCTION.

Narrative: I REALIZED I HAD A RADIO FAILURE AS I WAS HANDED OFF FROM CHARLESTON APCH TO ZID. I COULD RECEIVE, HOWEVER, I COULD NOT XMIT -- CARRIER NO VOICE. APPROX 10 MINS BEFOREHAND, I WAS GETTING A HIGH-PITCHED HUM OVER ALL MY HEADSETS AND ACFT SPEAKER THAT HAD INCREASED IN INTENSITY TO ANNOYING PROPORTIONS. I WAS AT THE POINT OF HDOF PASSING OVERHEAD AN ARPT. I DID NOT WANT TO CONTINUE THE FLT. I COULD STILL HEAR ZID. BEING OVERTOP THIS ARPT, MY THOUGHT WAS TO PROCEED VFR, LAND QUICKLY AND TO CALL IN. I DID NOT SQUAWK 7700/7600 IMMEDIATELY BECAUSE, IN 1 MIN I WOULD HAVE BEEN OUT OF RADAR COVERAGE EITHER ON THE GND OR CLOSE TO LNDG AND ALL ATC MIGHT'VE SEEN IS THE EMER CODE 7700 AND THEN I DROP OUT OF SIGHT. IN RETROSPECT, I WAS OUT-THINKING THE CTLRS. AS I BANKED TOWARD THE ARPT IN QUESTION, DSNDING, I COULD NOW MAKE OUT THAT THIS ARPT HAD NOT YET OPENED. THERE WERE NO FACILITIES AND NO VISIBLE X'S ON THE RWY, AND I WOULD NOT BE ABLE TO CALL ANYONE. AT PRECISELY THIS MOMENT, ZID ASKED ME IF I WAS GOING BACK TO CRW TO IDENT. I FIGURED AT THAT POINT THAT WAS THE RIGHT THING TO DO. I RESPONDED AND HE CLRED ME TO CRW AT 4000. ALSO, AT THIS POINT, BEING AWARE OF HAVING LEFT MY ORIGINAL ALT TO MAKE A VFR DSCNT AND LNDG I HAD BETTER SQUAWK 7700/7600, BUT AT PRECISELY THIS MOMENT, ZID ASKED IF I HAD AN EMER. I DID NOT IDENT, RESPONDING IN THE NEGATIVE. SO, AT THAT POINT IT SEEMED CONTRADICTORY TO THEN SQUAWK 7700, AND WITH 1-WAY RADIO COM POSSIBLE, COUPLED WITH MY ABILITY TO REPLY BY XPONDER AND MY PROX TO CHARLESTON, I DECIDED NOT TO CHANGE MY CODE. FROM THIS POINT FROM THE TIME I FIRST REALIZED MY RADIO FAILURE IT WAS APPROX 2 MINS. THIS ALL HAPPENED VERY QUICKLY. THERE WAS NO CONFUSION THAT FOLLOWED. I WAS EASILY HANDED BACK TO CHARLESTON APCH WITHOUT A TFC CONFLICT. TFC AROUND CHARLESTON WAS LIGHT AND I EASILY LANDED WITHOUT INCIDENT OR DIFFICULTY. I WAS THEN ASKED TO CALL THE TWR. I DID SO AND TALKED TO THE SUPVR. HE MADE IT CLR THAT IT WOULD'VE BEEN EASIER FOR THEM IF I HAD SQUAWKED 7700/7600 IMMEDIATELY BEFORE LEAVING MY ALT.

Data retrieved from NASA's ASRS site as of July 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.