Narrative:

During an IFR filed flight to slc from puc, after being handed to slc approach in the provo area, I was flying at 14000 ft, in continuous moderate turbulence, VMC conditions. I requested lower. The controller gave me descent clearance to 13000 ft with vectors for runway 34R localizer. Shortly after my turn to the vector heading I reported slc airport in sight and expected to get a 'cleared for a visual....' the controller gave me 'descend to 12000 ft, expect visual approach for runway 35 closer in.' during my descent from 13000 ft to 12000 ft, I contacted unicom and arranged transportation for my passenger to get to the airline side of the airport. I descended to 11600 ft before realizing the controller did not give me a 'cleared for the visual,' but instead gave me 'descend to 12000 ft.' I immediately corrected back to 12000 ft and asked for lower again. The rest of the flight was uneventful. I feel the situation occurred because I was expecting the controller to give me 'cleared for the visual,' and not an altitude restr. In addition, at this phase of the flight I should not have been arranging transportation for my passenger. Turbulence played a small role in this situation.

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Original NASA ASRS Text

Title: AN ATX PLT, FLYING AN SMT, DSNDED BELOW HIS ASSIGNED ALT WHILE DISTR BY COMPANY RADIO AND ALSO BECAUSE HE WAS ANTICIPATING A CLRNC FOR A VISUAL APCH.

Narrative: DURING AN IFR FILED FLT TO SLC FROM PUC, AFTER BEING HANDED TO SLC APCH IN THE PROVO AREA, I WAS FLYING AT 14000 FT, IN CONTINUOUS MODERATE TURB, VMC CONDITIONS. I REQUESTED LOWER. THE CTLR GAVE ME DSCNT CLRNC TO 13000 FT WITH VECTORS FOR RWY 34R LOC. SHORTLY AFTER MY TURN TO THE VECTOR HDG I RPTED SLC ARPT IN SIGHT AND EXPECTED TO GET A 'CLRED FOR A VISUAL....' THE CTLR GAVE ME 'DSND TO 12000 FT, EXPECT VISUAL APCH FOR RWY 35 CLOSER IN.' DURING MY DSCNT FROM 13000 FT TO 12000 FT, I CONTACTED UNICOM AND ARRANGED TRANSPORTATION FOR MY PAX TO GET TO THE AIRLINE SIDE OF THE ARPT. I DSNDED TO 11600 FT BEFORE REALIZING THE CTLR DID NOT GIVE ME A 'CLRED FOR THE VISUAL,' BUT INSTEAD GAVE ME 'DSND TO 12000 FT.' I IMMEDIATELY CORRECTED BACK TO 12000 FT AND ASKED FOR LOWER AGAIN. THE REST OF THE FLT WAS UNEVENTFUL. I FEEL THE SIT OCCURRED BECAUSE I WAS EXPECTING THE CTLR TO GIVE ME 'CLRED FOR THE VISUAL,' AND NOT AN ALT RESTR. IN ADDITION, AT THIS PHASE OF THE FLT I SHOULD NOT HAVE BEEN ARRANGING TRANSPORTATION FOR MY PAX. TURB PLAYED A SMALL ROLE IN THIS SIT.

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.