Narrative:

Upon departure from runway 16R at ZZZ; I entered IMC flying by my primary flight instruments (6-PACK). Upon entering IMC; I began to receive conflicting directional information between my HSI and GPS. I determined that my attitude indicator was giving correct information and held wings level until clearing IMC and reaching VFR on top. During this time I was queried by ATC regarding my heading. I advised I was having an issue with my navigation equipment. When I entered VFR; I requested assistance in the form of a heading and altitude so I could attempt to identify and rectify the problem. I was advised by ATC to return to ZZZ. I declined this request as PIC and advised ATC that it was not safe due to faulty and/or conflicting navigation information being received. A return to ZZZ would have mandated an instrument approach procedure back through IMC; an approach that I determined to be unsafe and life threatening. Upon reaching the assigned altitude and heading; I attempted to troubleshoot the problem and determined that the slaving unit for the HSI had become inoperative and that the HSI had precessed significantly shortly after gear retraction and upon entering IMC; causing the deviation from my assigned course. After manually slaving the HSI and determining that the HSI was reflecting correct navigation information with the automatic slaving unit turned off; I advised ATC that I had resolved the issue and requested to continue to my destination; which I knew was experiencing VFR WX. ATC advised that I had lost separation with another IFR aircraft during this incident and advised me to contact FSS.

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Original NASA ASRS Text

Title: FAILED GYRO SLAVING UNIT RESULTS IN TRACK DEVIATIONS AND LOSS OF SEPARATION FOR IFR BE58 PLT.

Narrative: UPON DEP FROM RWY 16R AT ZZZ; I ENTERED IMC FLYING BY MY PRIMARY FLT INSTS (6-PACK). UPON ENTERING IMC; I BEGAN TO RECEIVE CONFLICTING DIRECTIONAL INFO BTWN MY HSI AND GPS. I DETERMINED THAT MY ATTITUDE INDICATOR WAS GIVING CORRECT INFO AND HELD WINGS LEVEL UNTIL CLRING IMC AND REACHING VFR ON TOP. DURING THIS TIME I WAS QUERIED BY ATC REGARDING MY HDG. I ADVISED I WAS HAVING AN ISSUE WITH MY NAV EQUIP. WHEN I ENTERED VFR; I REQUESTED ASSISTANCE IN THE FORM OF A HDG AND ALT SO I COULD ATTEMPT TO IDENT AND RECTIFY THE PROB. I WAS ADVISED BY ATC TO RETURN TO ZZZ. I DECLINED THIS REQUEST AS PIC AND ADVISED ATC THAT IT WAS NOT SAFE DUE TO FAULTY AND/OR CONFLICTING NAV INFO BEING RECEIVED. A RETURN TO ZZZ WOULD HAVE MANDATED AN INST APCH PROC BACK THROUGH IMC; AN APCH THAT I DETERMINED TO BE UNSAFE AND LIFE THREATENING. UPON REACHING THE ASSIGNED ALT AND HDG; I ATTEMPTED TO TROUBLESHOOT THE PROB AND DETERMINED THAT THE SLAVING UNIT FOR THE HSI HAD BECOME INOP AND THAT THE HSI HAD PRECESSED SIGNIFICANTLY SHORTLY AFTER GEAR RETRACTION AND UPON ENTERING IMC; CAUSING THE DEV FROM MY ASSIGNED COURSE. AFTER MANUALLY SLAVING THE HSI AND DETERMINING THAT THE HSI WAS REFLECTING CORRECT NAV INFO WITH THE AUTOMATIC SLAVING UNIT TURNED OFF; I ADVISED ATC THAT I HAD RESOLVED THE ISSUE AND REQUESTED TO CONTINUE TO MY DEST; WHICH I KNEW WAS EXPERIENCING VFR WX. ATC ADVISED THAT I HAD LOST SEPARATION WITH ANOTHER IFR ACFT DURING THIS INCIDENT AND ADVISED ME TO CONTACT FSS.

Data retrieved from NASA's ASRS site as of May 2009 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.