PA46 HAS HSI FAILURE DEPARTING LAS.

Narrative

I HAD FILED AN IFR FLT TO SNA. MY INITIAL INSTRUCTIONS WERE TO FLY L TO 175 DEGS; AND FOR RADAR VECTORS TO THE INSTRUCTED AIRWAY. THAT WAS CHANGED AS THE RWY IN USE WAS ALSO BEING CHANGED. THE NEW INSTRUCTIONS WERE TO FLY 'HDG' 100 DEGS; WITH THE SAME; VECTORS ONTO THE AIRWAY. THERE WAS A 1 HR GND DELAY AS IT WAS BECOMING VERY BUSY; AND WE TAXIED AND HELD AT SEVERAL DIFFERENT LOCATIONS ON THE FIELD. DURING ONE POINT IN THE TAXI; WE HEARD AN AUDIBLE BEEP THAT I; OR THE OWNER OF THE PLANE; COULD NOT FIGURE OUT UNTIL I HIT THE AUTOPLT TEST SWITCH (FOR A SECOND TIME; ALREADY CHKED IN THE RUN-UP AND EQUIP TEST). THIS STOPPED THE BEEP. ALL FLT INSTS AND AVIONICS WERE SET AND CHKED TO BE WORKING PROPERLY. WHEN WE WERE FINALLY HOLDING SHORT OF RWY 7 AT TXWY D; THE OWNER OF THE PLANE WAS PIC AND WOULD HANDLE THE TKOF AND DEP. OUR DISCUSSION WAS FOR HOW HE WAS TO HANDLE THE STRONG AND GUSTY XWIND. IT MUST HAVE BEEN AT THIS TIME THAT THE HSI ON THE PLT SIDE BECAME INOP AND IN ERROR. AS WE DEPARTED; AT AN ESTIMATED 400-500 FT AGL; THE CTL TWR OPERATOR INSTRUCTED FOR US TO TURN TO A HDG OF 100 DEGS. THE PLT IN THE L SEAT CLRED TO THE L AND BEGAN TURNING. I LOOKED AT THE HSI ON THE PLT'S SIDE; AND SAW THE TURN WAS ABOUT 20 DEGS TO THE L. THIS WAS THE FIRST PUZZLING THING IN MY MIND AS THE OWNER TURNED TOWARD THE HDG BUG. MY SCAN WENT ELSEWHERE FOR A SHORT MOMENT AND WHEN I LOOKED BACK AT THE HDG ON THE HSI; I IMMEDIATELY TOLD HIM; 'I HAVE THE CTLS; HSI FAILURE!' RIGHT THEN THE CTLR ASKED US 'ACFT X; HOW DO YOU READ?' I TOLD HIM AT THAT MOMENT; 'WE HAVE A DIRECTIONAL GYRO FAILURE AND NEED A HDG IN DEGS RELATIVE TO OUR HDG.' I WAS NOW LOOKING TO THE WET COMPASS FOR THE HDG INFO. I ALSO HAD A SECOND HSI ON MY SIDE (L SEAT); AND OPTED NOT TO USE IT FOR THAT MOMENT. WE WERE GIVEN VECTORS TO HDGS; WHICH I STEERED TOWARD THE CORRECT COURSES THAT THE CTLR INSTRUCTED. EITHER WAY; THE COMPASS SUFFICED; CONSIDERING THE MODERATE TURB ON TKOF. WE WERE ASKED IF WE NEEDED TO RETURN TO LAND. I KNEW I WOULD PREFER TO TRY TO SORT IT OUT FIRST INFLT; AND ALSO PERHAPS IT IF WAS NOT FIXABLE; I COULD LAND ELSEWHERE SAFELY WHERE THERE WAS NO GND DELAYS. I PULLED AND RESET THE #1 HSI CIRCUIT BREAKER; AND IN A SHORT MOMENT THE #1 HSI CAME TO LIFE; WHICH ALSO AGREED WITH THE MAGNETIC COMPASS. ALSO; THE #1 NAV RADIO WAS INOP; AND THE NEEDLE CAME TO LIFE AND READ SENSIBLE. WE WERE USING THE GPS FOR GUIDANCE TOWARD THE AIRWAY; WHICH WE SET UP ON THE GND PRIOR TO TKOF. WE FELT WE WERE ABLE TO CONTINUE THE FLT WITH NO FURTHER ISSUES. ABOUT 45 MINS INTO THE FLT; THE #1 ALTERNATOR FAILED. WE RECYCLED THE #1 ALTERNATOR SWITCH; AND THE ALTERNATOR ANNUNCIATOR LIGHT WENT OUT TEMPORARILY. ABOUT 10 MINS LATER THE ANNUNCIATOR LIGHT BECAME INTERMITTENT. I RECYCLED THE SWITCH 1 OR 2 MORE TIMES; AND AFTER A SHORT WHILE THE ANNUNCIATOR LIGHT REMAINED ON; SO I SHUT IT OFF #1 ALTERNATOR AND USED ONLY THE #2 ALTERNATOR; AS PER THE POH INSTRUCTIONS. I WILL NOT FLY THIS PLANE AGAIN UNTIL I SEE THAT SOMEONE WORKS ON IT; AND I CAN TALK TO THE MECH TO FIND OUT WHAT WAS WRONG WITH IT. THE MAJOR LESSON BY ME IS TO ALWAYS INCLUDE A FINAL DIRECTIONAL GYRO CHK WHEN LINING UP ON CTRLINE OF THE RWY. I WAS COMPLACENT TO THE KNOWLEDGE THAT THE HSI WAS SLAVED; AND THAT IT SET ITSELF WHERE IT WAS SUPPOSED TO BE. THE L TURN OUT SHOULD HAVE BEEN AN OBVIOUS TELLTALE SIGN IMMEDIATELY THAT SOMETHING WAS INCORRECT; BUT MY COMMON SENSE WAS OVERRIDDEN BY MY CONFIDENCE IN THE INSTRUMENTATION. THIS; I WILL HAVE AS A LIFE-LONG EXPERIENCE TO GIVE TO ALL OF MY STUDENTS.