Narrative:

Apr/wed/00. Flight from kennedy space center (space coast regional tix) to sarasota/bradenton (srq). Upon landing, radios went 'stuck microphone' and remained so for approximately 5 mins. Once the microphone cleared, tower instructed to not key microphone and provided instructions that I acknowledged by cycling landing lights (night landing). Plane sent into avionics shop on field. Reported no observed problems with radios. Requested they check again. Reported again that no radio problems could be found. Apr/sat/00. Departed srq IFR for huntsville, al. Due to strong headwinds and weak bladders, diverted to birmingham. Fueled plane and filed new IFR flight plan to hfy (greenwood, in). Upon departure, cleared to 6000 ft by departure. Entered clouds at about 5000 ft MSL. Leveled at 6000 ft and reported 'level at 6000 ft,' whereupon microphone stuck open. Broadcast 'suspect stuck microphone, listening 112.8' (decatur VOR). Had all personnel in aircraft disconnect headsets. Disconnected own headset microphone lead and plugged in handheld microphone. Microphone continued stuck. Reported 'suspect stuck microphone, listening 112.8' repeatedly during duration on this time period. Switched from communication #1 to communication #2 and back repeatedly without benefit. Began to pick up light rime ice. Microphone began to break so that I was able to hear ATC occasionally. Heard request to change to 118.6 and complied on communication #2. Broadcast and was again told to change to 118.6. Confirmed I was on 118.6 and reported same. Changed communication #1 to 118.6 and switched to communication #1. Microphone continued intermittent sticking. Requested 4000 ft and reported light rime ice. Never able to hear clearance to 4000 ft due to microphone cutting in and out. Finally requested emergency descent to 4000 ft due to icing and began descent. During descent, I heard a clearance to 4000 ft. During descent, continued to try to clear radio problems and requested emergency clearance to huntsville airport. Radio began to behave better. ATC asked if I wanted to divert to folsom field (closer). I inquired if they had an avionics shop on the field. ATC checked and reported they could not verify if an avionics shop existed on the field. I requested continuation to huntsville. At this point, realized I had descended to approximately 3600 ft and immediately reported 'busted altitude, climbing from 3600 ft to 4000 ft.' ATC immediately cleared me to 2500 ft and cleared me for the approach to runway 36L at huntsville. ATC then inquired if an emergency still existed. I reported that the ice had cleared, I was out of the clouds and the radio seemed to be operating correctly and therefore the emergency had cleared. I was offered runway 36R (longer runway) following a B737. I elected to land runway 36L. Flight concluded without further incident. Concluded flight home apr/sun/00 VFR without further radio problems. Push-to-talk leads internal to the yoke have subsequently been found to be worn and intermittently shorting. Have since requested feedback from FSS and AOPA and only suggestions were switch to 121.5 when I suspected I was trashing the departure/approach frequencys and listen VOR as I did. Downside of this option is trashing the emergency frequency. Option to squawk 7600 was discussed and advised no real need to as I was broadcasting and ATC was aware of problems. Had icing been worse, I would have declared the emergency sooner. Other than that, do not know what I could have done differently.

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Original NASA ASRS Text

Title: A PA32 PVT PLT LOSES COM CAPABILITY WITH DEP CTL, ENCOUNTERS ICING AND EVENTUALLY DIVERTS TO ANOTHER ARPT WITH 20 MI N OF BHM, AL.

Narrative: APR/WED/00. FLT FROM KENNEDY SPACE CTR (SPACE COAST REGIONAL TIX) TO SARASOTA/BRADENTON (SRQ). UPON LNDG, RADIOS WENT 'STUCK MIKE' AND REMAINED SO FOR APPROX 5 MINS. ONCE THE MIKE CLRED, TWR INSTRUCTED TO NOT KEY MIKE AND PROVIDED INSTRUCTIONS THAT I ACKNOWLEDGED BY CYCLING LNDG LIGHTS (NIGHT LNDG). PLANE SENT INTO AVIONICS SHOP ON FIELD. RPTED NO OBSERVED PROBS WITH RADIOS. REQUESTED THEY CHK AGAIN. RPTED AGAIN THAT NO RADIO PROBS COULD BE FOUND. APR/SAT/00. DEPARTED SRQ IFR FOR HUNTSVILLE, AL. DUE TO STRONG HEADWINDS AND WEAK BLADDERS, DIVERTED TO BIRMINGHAM. FUELED PLANE AND FILED NEW IFR FLT PLAN TO HFY (GREENWOOD, IN). UPON DEP, CLRED TO 6000 FT BY DEP. ENTERED CLOUDS AT ABOUT 5000 FT MSL. LEVELED AT 6000 FT AND RPTED 'LEVEL AT 6000 FT,' WHEREUPON MIKE STUCK OPEN. BROADCAST 'SUSPECT STUCK MIKE, LISTENING 112.8' (DECATUR VOR). HAD ALL PERSONNEL IN ACFT DISCONNECT HEADSETS. DISCONNECTED OWN HEADSET MIKE LEAD AND PLUGGED IN HANDHELD MIKE. MIKE CONTINUED STUCK. RPTED 'SUSPECT STUCK MIKE, LISTENING 112.8' REPEATEDLY DURING DURATION ON THIS TIME PERIOD. SWITCHED FROM COM #1 TO COM #2 AND BACK REPEATEDLY WITHOUT BENEFIT. BEGAN TO PICK UP LIGHT RIME ICE. MIKE BEGAN TO BREAK SO THAT I WAS ABLE TO HEAR ATC OCCASIONALLY. HEARD REQUEST TO CHANGE TO 118.6 AND COMPLIED ON COM #2. BROADCAST AND WAS AGAIN TOLD TO CHANGE TO 118.6. CONFIRMED I WAS ON 118.6 AND RPTED SAME. CHANGED COM #1 TO 118.6 AND SWITCHED TO COM #1. MIKE CONTINUED INTERMITTENT STICKING. REQUESTED 4000 FT AND RPTED LIGHT RIME ICE. NEVER ABLE TO HEAR CLRNC TO 4000 FT DUE TO MIKE CUTTING IN AND OUT. FINALLY REQUESTED EMER DSCNT TO 4000 FT DUE TO ICING AND BEGAN DSCNT. DURING DSCNT, I HEARD A CLRNC TO 4000 FT. DURING DSCNT, CONTINUED TO TRY TO CLR RADIO PROBS AND REQUESTED EMER CLRNC TO HUNTSVILLE ARPT. RADIO BEGAN TO BEHAVE BETTER. ATC ASKED IF I WANTED TO DIVERT TO FOLSOM FIELD (CLOSER). I INQUIRED IF THEY HAD AN AVIONICS SHOP ON THE FIELD. ATC CHKED AND RPTED THEY COULD NOT VERIFY IF AN AVIONICS SHOP EXISTED ON THE FIELD. I REQUESTED CONTINUATION TO HUNTSVILLE. AT THIS POINT, REALIZED I HAD DSNDED TO APPROX 3600 FT AND IMMEDIATELY RPTED 'BUSTED ALT, CLBING FROM 3600 FT TO 4000 FT.' ATC IMMEDIATELY CLRED ME TO 2500 FT AND CLRED ME FOR THE APCH TO RWY 36L AT HUNTSVILLE. ATC THEN INQUIRED IF AN EMER STILL EXISTED. I RPTED THAT THE ICE HAD CLRED, I WAS OUT OF THE CLOUDS AND THE RADIO SEEMED TO BE OPERATING CORRECTLY AND THEREFORE THE EMER HAD CLRED. I WAS OFFERED RWY 36R (LONGER RWY) FOLLOWING A B737. I ELECTED TO LAND RWY 36L. FLT CONCLUDED WITHOUT FURTHER INCIDENT. CONCLUDED FLT HOME APR/SUN/00 VFR WITHOUT FURTHER RADIO PROBS. PUSH-TO-TALK LEADS INTERNAL TO THE YOKE HAVE SUBSEQUENTLY BEEN FOUND TO BE WORN AND INTERMITTENTLY SHORTING. HAVE SINCE REQUESTED FEEDBACK FROM FSS AND AOPA AND ONLY SUGGESTIONS WERE SWITCH TO 121.5 WHEN I SUSPECTED I WAS TRASHING THE DEP/APCH FREQS AND LISTEN VOR AS I DID. DOWNSIDE OF THIS OPTION IS TRASHING THE EMER FREQ. OPTION TO SQUAWK 7600 WAS DISCUSSED AND ADVISED NO REAL NEED TO AS I WAS BROADCASTING AND ATC WAS AWARE OF PROBS. HAD ICING BEEN WORSE, I WOULD HAVE DECLARED THE EMER SOONER. OTHER THAN THAT, DO NOT KNOW WHAT I COULD HAVE DONE DIFFERENTLY.

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.