Narrative:

We were en route from psp to ccr. Approximately 80 NM south of concord we observed a black wall of rain across our flight path. I turned northeast to avoid the WX. I found the WX was closing us off and decided to set down at mer. We waited out the storm on the ground for approximately 3 hours. The WX improved and we could see approximately 20 mi to the west and north. A plane arrived at castle and the 2 pilots told us the WX was clear and improving. Since we could see at least 10 mi and had a ceiling of approximately 1500 ft we decided to continue. After takeoff we proceeded north. Approximately 5 mi south of modesto we were instantly enveloped by clouds and strong wind. I set my VOR to 114.6 which is modesto and attempted to contact modesto tower 125.3. I made several calls and didn't receive any acknowledgment. I continued to transmit in the blind and advised I was landing modesto. I had good ground visibility and was able to recognize the field. I immediately set the plane down on runway 28. As I taxied off the field I was given a green light. I contacted ground on my hand-held radio to advise the tower of my problem. I next found one of my selector switches in the off position, reset the switch and the radio was working again. The spring on the switch was not holding the switch on and probably was knocked into the neutral position during the turbulence we encountered. The switch has since been replaced. There was no real danger to us but we did land at a field in IMC without clearance. The tower chastised us pretty well but they were also very helpful and understanding.

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Original NASA ASRS Text

Title: C182 PLT ENCOUNTERED WX AND HAD VHF COM PROB. LANDED AT MOD, NO COM.

Narrative: WE WERE ENRTE FROM PSP TO CCR. APPROX 80 NM S OF CONCORD WE OBSERVED A BLACK WALL OF RAIN ACROSS OUR FLT PATH. I TURNED NE TO AVOID THE WX. I FOUND THE WX WAS CLOSING US OFF AND DECIDED TO SET DOWN AT MER. WE WAITED OUT THE STORM ON THE GND FOR APPROX 3 HRS. THE WX IMPROVED AND WE COULD SEE APPROX 20 MI TO THE W AND N. A PLANE ARRIVED AT CASTLE AND THE 2 PLTS TOLD US THE WX WAS CLR AND IMPROVING. SINCE WE COULD SEE AT LEAST 10 MI AND HAD A CEILING OF APPROX 1500 FT WE DECIDED TO CONTINUE. AFTER TKOF WE PROCEEDED N. APPROX 5 MI S OF MODESTO WE WERE INSTANTLY ENVELOPED BY CLOUDS AND STRONG WIND. I SET MY VOR TO 114.6 WHICH IS MODESTO AND ATTEMPTED TO CONTACT MODESTO TWR 125.3. I MADE SEVERAL CALLS AND DIDN'T RECEIVE ANY ACKNOWLEDGMENT. I CONTINUED TO XMIT IN THE BLIND AND ADVISED I WAS LNDG MODESTO. I HAD GOOD GND VISIBILITY AND WAS ABLE TO RECOGNIZE THE FIELD. I IMMEDIATELY SET THE PLANE DOWN ON RWY 28. AS I TAXIED OFF THE FIELD I WAS GIVEN A GREEN LIGHT. I CONTACTED GND ON MY HAND-HELD RADIO TO ADVISE THE TWR OF MY PROB. I NEXT FOUND ONE OF MY SELECTOR SWITCHES IN THE OFF POS, RESET THE SWITCH AND THE RADIO WAS WORKING AGAIN. THE SPRING ON THE SWITCH WAS NOT HOLDING THE SWITCH ON AND PROBABLY WAS KNOCKED INTO THE NEUTRAL POS DURING THE TURB WE ENCOUNTERED. THE SWITCH HAS SINCE BEEN REPLACED. THERE WAS NO REAL DANGER TO US BUT WE DID LAND AT A FIELD IN IMC WITHOUT CLRNC. THE TWR CHASTISED US PRETTY WELL BUT THEY WERE ALSO VERY HELPFUL AND UNDERSTANDING.

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.