Narrative:

I was returning to salt lake city from big piney, wy. We were proceeding direct to lho VOR for the brigham city arrival into slc when approximately 20 mi northeast of cartr intersection, my GPS began showing signs of failing. It began indicating multiple headings to cartr. Almost immediately, my transponder quit working. By this time, we are over cartr intersection. Just prior (about 2 mins) the center controller asked for a position report. I told him we were 15 mi north of cartr. The next controller (approach) asked my position and altitude over cartr or just past cartr. I was trying to make the altitude readout work for them and told him I was at 14500 ft when I was actually at 15000 ft assigned. The standby position was selected on the altimeter. My position that I gave him was estimated. After all this, the controller asked me if I could make my landing at salt lake from a straight-in approach. I told him yes, but was then instructed to make a left 360 degree turn, which I did. Approach and landing were uneventful from that point. Being so close in to the airport, with multiple failures occurring with my equipment, may have contributed to a position report that was less than accurate.

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Original NASA ASRS Text

Title: A CPR CAPT EXPERIENCED A GPS FAILURE AND IS CONCERNED THAT HE MAY HAVE MADE AN ERRONEOUS POS RPT.

Narrative: I WAS RETURNING TO SALT LAKE CITY FROM BIG PINEY, WY. WE WERE PROCEEDING DIRECT TO LHO VOR FOR THE BRIGHAM CITY ARR INTO SLC WHEN APPROX 20 MI NE OF CARTR INTXN, MY GPS BEGAN SHOWING SIGNS OF FAILING. IT BEGAN INDICATING MULTIPLE HDGS TO CARTR. ALMOST IMMEDIATELY, MY XPONDER QUIT WORKING. BY THIS TIME, WE ARE OVER CARTR INTXN. JUST PRIOR (ABOUT 2 MINS) THE CTR CTLR ASKED FOR A POS RPT. I TOLD HIM WE WERE 15 MI N OF CARTR. THE NEXT CTLR (APCH) ASKED MY POS AND ALT OVER CARTR OR JUST PAST CARTR. I WAS TRYING TO MAKE THE ALT READOUT WORK FOR THEM AND TOLD HIM I WAS AT 14500 FT WHEN I WAS ACTUALLY AT 15000 FT ASSIGNED. THE STANDBY POS WAS SELECTED ON THE ALTIMETER. MY POS THAT I GAVE HIM WAS ESTIMATED. AFTER ALL THIS, THE CTLR ASKED ME IF I COULD MAKE MY LNDG AT SALT LAKE FROM A STRAIGHT-IN APCH. I TOLD HIM YES, BUT WAS THEN INSTRUCTED TO MAKE A L 360 DEG TURN, WHICH I DID. APCH AND LNDG WERE UNEVENTFUL FROM THAT POINT. BEING SO CLOSE IN TO THE ARPT, WITH MULTIPLE FAILURES OCCURRING WITH MY EQUIP, MAY HAVE CONTRIBUTED TO A POS RPT THAT WAS LESS THAN ACCURATE.

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.