Narrative:

Made a flight from 6a8 to mwc. Descent from 16000' was solid IMC. Mwc was reporting 800/1. Preparing for the approach (VOR 4L), I was receiving both ljt and bae. Just as I was cleared for the approach, I quit reading ljt. I tried both VOR's and had no deflection. I could read bae. I also had DME and a morse identify on ljt. I informed ATC, who suggested the localizer 15L approach. I agreed, but during vectors to the approach found that reception was intermittent. I flew through the first approach fix with no deflection, but as I returned for a second attempt, I received a signal. It quit again at the MDA, but I had the field in sight. I circled to runway 4 and continued my descent. It was snowing hard at this time, and I lost sight of the airport (the ground was visible). I attempted to find the airport with major concern over the inoperative VOR's. I was advised by the tower that approach had called with a low altitude alert. I promptly started the missed approach procedure and called approach control. Shortly thereafter, I found both VOR's working normally. I requested and received clearance for the VOR 4L approach and landed west/O further incident. I have no explanation for the VOR failure, other than ice on the antenna, which may have melted in my low approach ground temperature was 33 degrees F. I observed only very light rime ice on the leading edge of the wing. At all times, the DME and morse identify were received.

Related reports:

Google
 

Original NASA ASRS Text

Title: SMA PLT MAKING CIRCLING APCH LOSES SIGHT OF ARPT, BUT ATTEMPTS TO CONTINUE APCH UNTIL WARNED OF LOW ALT ALERT BY ATC.

Narrative: MADE A FLT FROM 6A8 TO MWC. DSCNT FROM 16000' WAS SOLID IMC. MWC WAS RPTING 800/1. PREPARING FOR THE APCH (VOR 4L), I WAS RECEIVING BOTH LJT AND BAE. JUST AS I WAS CLRED FOR THE APCH, I QUIT READING LJT. I TRIED BOTH VOR'S AND HAD NO DEFLECTION. I COULD READ BAE. I ALSO HAD DME AND A MORSE IDENT ON LJT. I INFORMED ATC, WHO SUGGESTED THE LOC 15L APCH. I AGREED, BUT DURING VECTORS TO THE APCH FOUND THAT RECEPTION WAS INTERMITTENT. I FLEW THROUGH THE FIRST APCH FIX WITH NO DEFLECTION, BUT AS I RETURNED FOR A SECOND ATTEMPT, I RECEIVED A SIGNAL. IT QUIT AGAIN AT THE MDA, BUT I HAD THE FIELD IN SIGHT. I CIRCLED TO RWY 4 AND CONTINUED MY DSCNT. IT WAS SNOWING HARD AT THIS TIME, AND I LOST SIGHT OF THE ARPT (THE GND WAS VISIBLE). I ATTEMPTED TO FIND THE ARPT WITH MAJOR CONCERN OVER THE INOP VOR'S. I WAS ADVISED BY THE TWR THAT APCH HAD CALLED WITH A LOW ALT ALERT. I PROMPTLY STARTED THE MISSED APCH PROC AND CALLED APCH CTL. SHORTLY THEREAFTER, I FOUND BOTH VOR'S WORKING NORMALLY. I REQUESTED AND RECEIVED CLRNC FOR THE VOR 4L APCH AND LANDED W/O FURTHER INCIDENT. I HAVE NO EXPLANATION FOR THE VOR FAILURE, OTHER THAN ICE ON THE ANTENNA, WHICH MAY HAVE MELTED IN MY LOW APCH GND TEMP WAS 33 DEGS F. I OBSERVED ONLY VERY LIGHT RIME ICE ON THE LEADING EDGE OF THE WING. AT ALL TIMES, THE DME AND MORSE IDENT WERE RECEIVED.

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.