Narrative:

On VFR flight from bakersfield, ca, to santa maria, ca, approximately 75 NM flying above scattered cloud layer. Cloud layer above became broken to overcast. Maintained VFR. Attempted calls to ZLA on 119.05 to no avail. Letdown VFR through scattered layer approximately 15 NM southeast of santa maria airport. Proceeding northwest toward airport attempting contact requesting SVFR landing, no response until at airport east side. Advised by tower that airport was IFR and my xmissions were broken and to contact ZLA for IFR. Advised tower that I was unable to contact ZLA and desired to land immediately since I could not maintain VFR much longer. While circling the field, I was aware that no aircraft were departing as I could see runway and could hear no other traffic. Advised to land and contact tower. Told I was in violation of entering class D area without radio contact. Subsequent examination of microphone revealed my boom microphone was shorting out causing all communication difficulties. Subsequently, I repaired loose boom microphone connection. In summary, with poor and intermittent communications in marginal to IFR conditions at the airport below me, the only safe action was to land, especially since there was no other noted traffic in the area.

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Original NASA ASRS Text

Title: A MOONEY 20C PLT HAS A MIKE PROB AND PERFORMS AN UNAUTH PENETRATION OF SMX CLASS D AIRSPACE. WX WAS 800 FT AND 1 MI.

Narrative: ON VFR FLT FROM BAKERSFIELD, CA, TO SANTA MARIA, CA, APPROX 75 NM FLYING ABOVE SCATTERED CLOUD LAYER. CLOUD LAYER ABOVE BECAME BROKEN TO OVCST. MAINTAINED VFR. ATTEMPTED CALLS TO ZLA ON 119.05 TO NO AVAIL. LETDOWN VFR THROUGH SCATTERED LAYER APPROX 15 NM SE OF SANTA MARIA ARPT. PROCEEDING NW TOWARD ARPT ATTEMPTING CONTACT REQUESTING SVFR LNDG, NO RESPONSE UNTIL AT ARPT E SIDE. ADVISED BY TWR THAT ARPT WAS IFR AND MY XMISSIONS WERE BROKEN AND TO CONTACT ZLA FOR IFR. ADVISED TWR THAT I WAS UNABLE TO CONTACT ZLA AND DESIRED TO LAND IMMEDIATELY SINCE I COULD NOT MAINTAIN VFR MUCH LONGER. WHILE CIRCLING THE FIELD, I WAS AWARE THAT NO ACFT WERE DEPARTING AS I COULD SEE RWY AND COULD HEAR NO OTHER TFC. ADVISED TO LAND AND CONTACT TWR. TOLD I WAS IN VIOLATION OF ENTERING CLASS D AREA WITHOUT RADIO CONTACT. SUBSEQUENT EXAMINATION OF MIKE REVEALED MY BOOM MIKE WAS SHORTING OUT CAUSING ALL COM DIFFICULTIES. SUBSEQUENTLY, I REPAIRED LOOSE BOOM MIKE CONNECTION. IN SUMMARY, WITH POOR AND INTERMITTENT COMS IN MARGINAL TO IFR CONDITIONS AT THE ARPT BELOW ME, THE ONLY SAFE ACTION WAS TO LAND, ESPECIALLY SINCE THERE WAS NO OTHER NOTED TFC IN THE AREA.

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.