Narrative:

I flew out of livermore and filed IFR. I was on the assigned byron 1 departure heading for the first waypoint, which was also the NDB (reiga) when everything went wrong. I had station passage, turned to 030 degrees, and the departure controller asked me why I was doing so. I told him (after very quickly doublechking the departure page) that I was right on course, etc, and he said I was really screwing up (other words than that but same meaning). I was very perplexed to say the least. I looked again at my ADF and it was now showing it sort of off my right instead of behind me as it should have been. I turned back to the NDB. Then I looked at the compass -- it was spinning around as if driven by a 100-200 RPM motor. In the past, I had seen that happen before. As I passed within about 1/4 mi of a 50000 watt am radio station in idaho, it had sent the compass spinning unctlably for nearly 3 mins. It took over 5 mins for it to stop spinning this time and the NDB required about 5 NM to respond correctly. Even the VOR and RNAV (kns-81) were somewhat affected and their readings were not reliable. It threw all my headings off. I could not reset the gyro for nearly 15 mins. Whatever high power radiation is in that area was fairly close to lvk, but not out as far as the NDB.

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Original NASA ASRS Text

Title: TB20 PLT ATTRIBUTES TEMPORARY LOSS OF NAV EQUIP TO HIGH PWR RADIATION SOURCE BTWN LVK AND REIGA (NDB).

Narrative: I FLEW OUT OF LIVERMORE AND FILED IFR. I WAS ON THE ASSIGNED BYRON 1 DEP HEADING FOR THE FIRST WAYPOINT, WHICH WAS ALSO THE NDB (REIGA) WHEN EVERYTHING WENT WRONG. I HAD STATION PASSAGE, TURNED TO 030 DEGS, AND THE DEP CTLR ASKED ME WHY I WAS DOING SO. I TOLD HIM (AFTER VERY QUICKLY DOUBLECHKING THE DEP PAGE) THAT I WAS RIGHT ON COURSE, ETC, AND HE SAID I WAS REALLY SCREWING UP (OTHER WORDS THAN THAT BUT SAME MEANING). I WAS VERY PERPLEXED TO SAY THE LEAST. I LOOKED AGAIN AT MY ADF AND IT WAS NOW SHOWING IT SORT OF OFF MY R INSTEAD OF BEHIND ME AS IT SHOULD HAVE BEEN. I TURNED BACK TO THE NDB. THEN I LOOKED AT THE COMPASS -- IT WAS SPINNING AROUND AS IF DRIVEN BY A 100-200 RPM MOTOR. IN THE PAST, I HAD SEEN THAT HAPPEN BEFORE. AS I PASSED WITHIN ABOUT 1/4 MI OF A 50000 WATT AM RADIO STATION IN IDAHO, IT HAD SENT THE COMPASS SPINNING UNCTLABLY FOR NEARLY 3 MINS. IT TOOK OVER 5 MINS FOR IT TO STOP SPINNING THIS TIME AND THE NDB REQUIRED ABOUT 5 NM TO RESPOND CORRECTLY. EVEN THE VOR AND RNAV (KNS-81) WERE SOMEWHAT AFFECTED AND THEIR READINGS WERE NOT RELIABLE. IT THREW ALL MY HDGS OFF. I COULD NOT RESET THE GYRO FOR NEARLY 15 MINS. WHATEVER HIGH PWR RADIATION IS IN THAT AREA WAS FAIRLY CLOSE TO LVK, BUT NOT OUT AS FAR AS THE NDB.

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.