AN A319 PIC'S RPT ON AN AUTOPLT MALFUNCTION THAT CREATED AN UNCOMMANDED CLB FROM INITIAL APCH ALT 30 MI S OF CLT; NC.

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AN AIRBUS 319 WAS ON FINAL APCH TO RWY 36R AT APPROX 25 DME; 3600 FT ASSIGNED. ACFT WAS DOING 160 KIAS ASSIGNED WITH GEAR UP AND FLAPS 2 DEGS. ACFT HAD CAPTURED THE RWY 36R ILS LOC AND WAS 5 MI IN TRAIL TO ILS RWY 36R WHEN ACFT SUDDENLY PITCHED UP APPROX 20-25 DEGS AND AUTOTHROTTLES WENT TO MAX THRUST. (AUTOPLTS 1 AND 2 WERE CONNECTED. ALT SET WAS 3600 FT.) ACFT REACHED APPROX 4200 FT MSL. AUTOPLT WAS SWITCHED OFF. AUTOTHRUST WAS DISENGAGED. ATC WAS NOTIFIED OF OUR PROBS WITH ACFT CTL AND THE AIRSPACE WAS CLRED AROUND US. WHILE DESCENDING TO 3600 FT AUTOTHRUST AGAIN WENT FULL FORWARD (MAX THRUST) WHILE RETRACTING THE FLAPS AND ACFT'S AIRSPD EXCEEDED 250 KIAS TO APPROX 270 KIAS. ALT DEV; ACFT WAS NOW AT APPROX 2800 FT. ACFT'S AUTOTHRUST WAS AGAIN DISCONNECTED AND AIRSPD AND ALT WERE STABILIZED. ATC GAVE US RADAR VECTORS TO THE FAC ILS RWY 36R. THE APCH WAS RE-ENTERED INTO THE FMGC AND THE APCH WAS CONTINUED AGAIN. AFTER AN UNEVENTFUL LNDG WE WERE UNABLE TO DETERMINE WHY THE ACFT SUDDENLY PITCHED NOSE-UP AND APPLIED FULL PWR. MAINT; SAFETY; TRAINING AND UNION WERE ADVISED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE REASON THE ACFT WAS 30 MI OUT AT THAT LOW ALT WAS THE HIGH WINDS ALOFT THAT WERE GIVING SPACING PROBS FOR ATC. THE WINDS AT 5000 FT WERE AT 70 KTS. THE CREW HAD THE A319 ON AUTOPLT; IN THE APCH CONFIGN. THAT CONFIGN SHOULD HAVE LOCKED IN THE SELECTED ALT TO AN ALT HOLD MODE. AT THIS POINT IT IS NOT KNOW WHY THE ACFT LEFT THE SELECTED ALT. THE APCH MODE SELECTION MAY BE A KEY. THE CAPT LOST SOME TIME PRIOR TO EFFECTING AN AUTOTHRUST DISCONNECT DUE TO NOT; INITIALLY; MATCHING THROTTLE POS TO THE CURRENT THRUST POS THAT WAS ASSUMED BY THE AUTOTHRUST. THIS AUTOTHRUST ACTIVATION WAS CAUSED BY THE FAULTY SENSING OF ACFT SPD BY THE TWO ANGLE OF ATTACK VANES LOCATED ON EACH SIDE OF THE ACFT. THEY ARE SENSORS THAT CAN; FOR STALL PROTECTION; DEFAULT THE AUTOTHRUST (EVEN IF DISCONNECTED) INTO A 'TOGA' MODE (CALLED 'ALPHA FLOOR') ACCELERATING THE ENGS BUT NOT MOVING THE THROTTLES. (POSTFLT DIAGNOSIS STATED THAT THE VANE SPD SENSING ENVELOPES WERE OUT OF TOLERANCE.) THE FO WAS RETRACTING THE FLAPS TO A FLAPS 1 POS AND THEN TO FLAPS 0 DURING THE NOSE OVER AT 4200 FT WHEN THE FAULTY SENSORS THEN REACTIVATED ALPHA FLOOR AND THE AUTOTHRUST INTO A STALL RECOVERY (TOGA) MODE AGAIN. AIRSPD WAS ABOVE 200 KTS AT THIS POINT; ACCELERATING THE ACFT TO 270 KTS. SUPPLEMENTAL INFO FROM ACN 461312: ON RWY 36R ILS CAT IIIB APCH CLT. I BELIEVE THIS A319'S AUTOPLT WAS FAULTY AND GAVE ERRONEOUS COMMANDS. THERE WAS NO REASON FOR THIS TO OCCUR. UNAWARE OF ANY FURTHER ACTION; TO MY KNOWLEDGE; THAT WOULD HAVE PREVENTED THIS.