Narrative:

I was on an IFR flight plan from nassau to ft lauderdale executive airport. My clearance route was: cleared to fxe br 57V report decal intersection, maintain 8000 ft. Nassau departure vectored me to intercept 57V which is the 314 degree radial from nassau VOR to carey intersection. I idented the intersection with the DME and turning to a heading of 280 degrees to track 57V to bimini. I was navigating using the #1 VOR. It indicated that I was drifting right away from the centerline of the airway. I was correcting for the drift when miami approach advised me that I was off the airway and, in fact, flying away from it. Approach gave me a heading to fly and told me to proceed direct bimini. I tuned the #2 VOR to bimini, idented, and used it to fly direct bimini. Within 30 NM of bimini the #1 VOR needle centered indicating that I was on the airway. Thus, I became aware that I had a problem with the #1 VOR. Both vors had been checked prior the flight, both were in tolerance. Inasmuch as I was vectored mostly during the flight to nassau, I didn't detect a problem with the #1 VOR. Subsequently, in-flight tests revealed that it was not reliable when greater than approximately 30-35 NM distance from a station, whether tracking to, or from the station. The #2 VOR functioned well, however both are being scheduled for shop testing and calibration.

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Original NASA ASRS Text

Title: PA32 PLT WANDERS OFF AIRWAY OVER WATER WHEN 1 OF 2 VOR RECEIVERS MALFUNCTIONS. CTLR SAVES THE DAY.

Narrative: I WAS ON AN IFR FLT PLAN FROM NASSAU TO FT LAUDERDALE EXECUTIVE ARPT. MY CLRNC RTE WAS: CLRED TO FXE BR 57V RPT DECAL INTXN, MAINTAIN 8000 FT. NASSAU DEP VECTORED ME TO INTERCEPT 57V WHICH IS THE 314 DEG RADIAL FROM NASSAU VOR TO CAREY INTXN. I IDENTED THE INTXN WITH THE DME AND TURNING TO A HDG OF 280 DEGS TO TRACK 57V TO BIMINI. I WAS NAVING USING THE #1 VOR. IT INDICATED THAT I WAS DRIFTING RIGHT AWAY FROM THE CTRLINE OF THE AIRWAY. I WAS CORRECTING FOR THE DRIFT WHEN MIAMI APCH ADVISED ME THAT I WAS OFF THE AIRWAY AND, IN FACT, FLYING AWAY FROM IT. APCH GAVE ME A HEADING TO FLY AND TOLD ME TO PROCEED DIRECT BIMINI. I TUNED THE #2 VOR TO BIMINI, IDENTED, AND USED IT TO FLY DIRECT BIMINI. WITHIN 30 NM OF BIMINI THE #1 VOR NEEDLE CTRED INDICATING THAT I WAS ON THE AIRWAY. THUS, I BECAME AWARE THAT I HAD A PROB WITH THE #1 VOR. BOTH VORS HAD BEEN CHKED PRIOR THE FLT, BOTH WERE IN TOLERANCE. INASMUCH AS I WAS VECTORED MOSTLY DURING THE FLT TO NASSAU, I DIDN'T DETECT A PROB WITH THE #1 VOR. SUBSEQUENTLY, INFLT TESTS REVEALED THAT IT WAS NOT RELIABLE WHEN GREATER THAN APPROX 30-35 NM DISTANCE FROM A STATION, WHETHER TRACKING TO, OR FROM THE STATION. THE #2 VOR FUNCTIONED WELL, HOWEVER BOTH ARE BEING SCHEDULED FOR SHOP TESTING AND CALIBRATION.

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.