Narrative:

After being handed off to la approach, our #1 VOR quit working. Shortly thereafter, we lost transmission capability and isolated the problem to a bad microphone. We could hear lax approach and communicated by pressing identify on transponder to acknowledge receipt and understanding of transmission. On the ground at lax, we worked on the problem and purchased a new microphone. All appeared in operating condition. Both radios transmission and receive capabilities were checked on both radios by receiving clearance and while talking to ground. While on departure, the transmission light stuck on as though I was transmitting. I pulled microphone jack out and light stayed on. Turned off radio and tried other microphone jack and microphone. No luck. My clearance was to expect vectors direct vtu VOR in 8 mi, so I turned direct. My clearance from ground was to expect 8000 5 min after departure, so I continued to climb to 8000. VMC conditions were present so I determined that land as soon as practicable meant home base, sbp. During this entire time, I would occasionally try to re-boot the system to check correct operation of radios. No luck. Finally, the problem disappeared somewhere near ventura and I was able to contact sba approach. Told that microphone was sticking and to contact lax center immediately. Before contacting lax approach, I verified with sba approach my intentions to fly to prb if communication lost again. Then contacted lax approach. No further failure. Though this incident did not apparently pose any traffic conflict, it may have backed traffic up and stopped communications in the la area due to a stuck microphone condition not having been identified soon enough. By turning off the radios, I was able to stop the problem, but consequently, lost communications. Everything in my bag of tricks was tried to bring the radios back on line, and was finally able to do so. Lax approach in the landing sequence did an excellent job in handling us on the way into lax. I didn't do an expedient job in identifying the stuck microphone on departure. Sba approach should not have been so quick to hand me off to lax center until my situation was determined to be under control and further lost communication intentions were identified. Since I was vme, should I have climbed to 8500 instead of 8000? I think not, since I was operating under IFR clearance. Since this was a rented aircraft, maintenance cannot be constantly supervised by the pilot. Both transmission and receive capabilities were checked prior to departure from sbp. The problem was reported to the owner/operator and sloughed off as pilot error. This I see as the cause rather than the effect or symptoms of the problem. Sba approach should understand that there needn't be any shortness of temper when problems occur and not to pass the problem off until all intentions are understood. Lax center was again very capable of handling the situation and needs to be thanked. Owner/operators need a more closely supervised maintenance program, especially if operating under the guise of nonprofit organizations. I do not believe any FARS or operating procedure were violated in this case, but do see this as a situation in which others can learn that all is not roses when radios appear to function well on the ground. During my repair attempts, altitude control was not as close to tolerances (ie, greater than) as it should have been due to reaching allover the cockpit for remedies. The other question which comes to mind: should I have squawked 7600? I thought not since I was already under IFR. Lessons learned? Carry a spare microphone, perhaps even purchase handheld radios. Callback conversation with reporter revealed following information. Reporter counseled on use transponder code 7700 then 7600 in case of communication failure. He reported had communication failure with the same aircraft few days later but the owner apparently doesn't believe him and won't do anything to the aircraft. Stated aircraft usually flown by mostly VFR pilots in club, so they are not aware of communication problem. Stated has had no feedback from ATC so figures only thing blocked was his transmission and reception so other traffic was not affected. Felt sba controller's attitude was poor but realizes they are busy.

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Original NASA ASRS Text

Title: GA SMA ON IFR FLT PLAN LOST RADIO COM.

Narrative: AFTER BEING HANDED OFF TO LA APCH, OUR #1 VOR QUIT WORKING. SHORTLY THEREAFTER, WE LOST XMISSION CAPABILITY AND ISOLATED THE PROB TO A BAD MICROPHONE. WE COULD HEAR LAX APCH AND COMMUNICATED BY PRESSING IDENT ON XPONDER TO ACKNOWLEDGE RECEIPT AND UNDERSTANDING OF XMISSION. ON THE GND AT LAX, WE WORKED ON THE PROB AND PURCHASED A NEW MICROPHONE. ALL APPEARED IN OPERATING CONDITION. BOTH RADIOS XMISSION AND RECEIVE CAPABILITIES WERE CHECKED ON BOTH RADIOS BY RECEIVING CLRNC AND WHILE TALKING TO GND. WHILE ON DEP, THE XMISSION LIGHT STUCK ON AS THOUGH I WAS XMITTING. I PULLED MICROPHONE JACK OUT AND LIGHT STAYED ON. TURNED OFF RADIO AND TRIED OTHER MIKE JACK AND MICROPHONE. NO LUCK. MY CLRNC WAS TO EXPECT VECTORS DIRECT VTU VOR IN 8 MI, SO I TURNED DIRECT. MY CLRNC FROM GND WAS TO EXPECT 8000 5 MIN AFTER DEP, SO I CONTINUED TO CLB TO 8000. VMC CONDITIONS WERE PRESENT SO I DETERMINED THAT LAND AS SOON AS PRACTICABLE MEANT HOME BASE, SBP. DURING THIS ENTIRE TIME, I WOULD OCCASIONALLY TRY TO RE-BOOT THE SYS TO CHK CORRECT OPERATION OF RADIOS. NO LUCK. FINALLY, THE PROB DISAPPEARED SOMEWHERE NEAR VENTURA AND I WAS ABLE TO CONTACT SBA APCH. TOLD THAT MICROPHONE WAS STICKING AND TO CONTACT LAX CENTER IMMEDIATELY. BEFORE CONTACTING LAX APCH, I VERIFIED WITH SBA APCH MY INTENTIONS TO FLY TO PRB IF COM LOST AGAIN. THEN CONTACTED LAX APCH. NO FURTHER FAILURE. THOUGH THIS INCIDENT DID NOT APPARENTLY POSE ANY TFC CONFLICT, IT MAY HAVE BACKED TFC UP AND STOPPED COMS IN THE LA AREA DUE TO A STUCK MICROPHONE CONDITION NOT HAVING BEEN IDENTIFIED SOON ENOUGH. BY TURNING OFF THE RADIOS, I WAS ABLE TO STOP THE PROB, BUT CONSEQUENTLY, LOST COMS. EVERYTHING IN MY BAG OF TRICKS WAS TRIED TO BRING THE RADIOS BACK ON LINE, AND WAS FINALLY ABLE TO DO SO. LAX APCH IN THE LNDG SEQUENCE DID AN EXCELLENT JOB IN HANDLING US ON THE WAY INTO LAX. I DIDN'T DO AN EXPEDIENT JOB IN IDENTIFYING THE STUCK MIKE ON DEP. SBA APCH SHOULD NOT HAVE BEEN SO QUICK TO HAND ME OFF TO LAX CENTER UNTIL MY SITUATION WAS DETERMINED TO BE UNDER CONTROL AND FURTHER LOST COM INTENTIONS WERE IDENTIFIED. SINCE I WAS VME, SHOULD I HAVE CLBED TO 8500 INSTEAD OF 8000? I THINK NOT, SINCE I WAS OPERATING UNDER IFR CLRNC. SINCE THIS WAS A RENTED ACFT, MAINT CANNOT BE CONSTANTLY SUPERVISED BY THE PLT. BOTH XMISSION AND RECEIVE CAPABILITIES WERE CHECKED PRIOR TO DEP FROM SBP. THE PROB WAS RPTED TO THE OWNER/OPERATOR AND SLOUGHED OFF AS PLT ERROR. THIS I SEE AS THE CAUSE RATHER THAN THE EFFECT OR SYMPTOMS OF THE PROB. SBA APCH SHOULD UNDERSTAND THAT THERE NEEDN'T BE ANY SHORTNESS OF TEMPER WHEN PROBS OCCUR AND NOT TO PASS THE PROB OFF UNTIL ALL INTENTIONS ARE UNDERSTOOD. LAX CENTER WAS AGAIN VERY CAPABLE OF HANDLING THE SITUATION AND NEEDS TO BE THANKED. OWNER/OPERATORS NEED A MORE CLOSELY SUPERVISED MAINT PROGRAM, ESPECIALLY IF OPERATING UNDER THE GUISE OF NONPROFIT ORGANIZATIONS. I DO NOT BELIEVE ANY FARS OR OPERATING PROC WERE VIOLATED IN THIS CASE, BUT DO SEE THIS AS A SITUATION IN WHICH OTHERS CAN LEARN THAT ALL IS NOT ROSES WHEN RADIOS APPEAR TO FUNCTION WELL ON THE GND. DURING MY REPAIR ATTEMPTS, ALT CONTROL WAS NOT AS CLOSE TO TOLERANCES (IE, GREATER THAN) AS IT SHOULD HAVE BEEN DUE TO REACHING ALLOVER THE COCKPIT FOR REMEDIES. THE OTHER QUESTION WHICH COMES TO MIND: SHOULD I HAVE SQUAWKED 7600? I THOUGHT NOT SINCE I WAS ALREADY UNDER IFR. LESSONS LEARNED? CARRY A SPARE MICROPHONE, PERHAPS EVEN PURCHASE HANDHELD RADIOS. CALLBACK CONVERSATION WITH RPTR REVEALED FOLLOWING INFO. RPTR COUNSELED ON USE TRANSPONDER CODE 7700 THEN 7600 IN CASE OF COM FAILURE. HE RPTED HAD COM FAILURE WITH THE SAME ACFT FEW DAYS LATER BUT THE OWNER APPARENTLY DOESN'T BELIEVE HIM AND WON'T DO ANYTHING TO THE ACFT. STATED ACFT USUALLY FLOWN BY MOSTLY VFR PLTS IN CLUB, SO THEY ARE NOT AWARE OF COM PROB. STATED HAS HAD NO FEEDBACK FROM ATC SO FIGURES ONLY THING BLOCKED WAS HIS XMISSION AND RECEPTION SO OTHER TFC WAS NOT AFFECTED. FELT SBA CTLR'S ATTITUDE WAS POOR BUT REALIZES THEY ARE BUSY.

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.