ACR WDB TAIL STRIKE ON LNDG.

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TAILSTRIKE AT LAX. WX CONDITIONS WERE VFR AND WINDS WERE NEAR CALM. A SLIGHT TAILWIND OF 3 KTS. APCH VIA VECTORS TO RWY 25L AT LAX AND BACKED UP BY ILS; HAND FLOWN WITH GOOD SMOOTH PRECISION EFFORTS BY F/O. ILS WAS ON CENTERLINE AND G/S; 50 DEG FLAPS WERE CALLED FOR SELECTED AND VERIFIED BTWN 1500' AND 1400' MSL; LNDG CHKLIST WAS COMPLETED. TARGET SPD WAS SET AT 136K; VREF #131K. APCH WAS FLOWN AT TARGET. ALT CALLOUTS WERE MADE. AT LESS THAN 50' A SLOW SMOOTH ROUND OUT AND PWR REDUCTION WAS STARTED. AT TIME OF 10' CALLOUT F/O SAID; 'WHERE IS THE GND?'; TO WHICH I REPLIED; 'YOU'RE THERE.' AT THAT MOMENT I NOTICED A PITCH ATTITUDE OF APPROX 10 DEGS AND PUT MY HAND OPEN PALM ON CENTER OF YOKE WITH INTENT OF FORWARD PRESSURE. AT THAT MOMENT AUTO SPOILERS DEPLOYED AND A SLIGHT THUD OF TAIL CONTACT WAS FELT. I THEN NOTICED PITCH ATTITUDE COMING DOWNWARD FROM 12 DEGS AND KNEW MY REACTION WAS NOT QUICK ENOUGH OR STRONG ENOUGH. LNDG ROLLOUT WAS SMOOTH AND NORMAL. TWR ASKED IF THEY POSSIBLY OBSERVED SPARKS FROM LNDG; TO WHICH WE REPLIED; 'POSSIBLY.' AFTER ARRIVING AT THE GATE A VISUAL CHK WAS MADE AND LOGBOOK WRITE-UP WAS ENTERED. A FOLLOW-UP WITH MAINT THE NEXT DAY CONFIRMED THAT NO STRUCTURAL DAMAGE WAS DONE (AND I THANK GOD FOR THAT!). POSSIBLE CORRECTIVE EFFORT: USE OF +10K OVER VREF FOR TARGET SPD WHEN LNDG WITH TAILWIND; AND QUICKER OR MORE SEVERE REACTION ON MY PART. SUPPLEMENTAL INFORMATION FROM ACN 81376: I SENSED A FAST RATE OF CLOSURE AND AT THE 50' CALL BEGAN A SLOW ROUNDOUT; FOLLOWED BY A FLARE AND SLOW CLOSING OF THE THROTTLES AT THE 30' CALL. IT THEN SEEMED TO ME I WAS HIGH AND FLOATING AND I APPLIED MORE AFT PRESSURE ON THE YOKE AND COMMENTED; 'WHERE'S THE GND?' T/D WAS NORMAL AND WITHIN THE T/D ZONE. UPON SPOILER DEPLOYMENT I REMEMBER NOW A SLIGHT BUMP IN THE CTLS; ALTHOUGH AT THE TIME I DID NOT RECOGNIZE IT.