ACFT DAMAGED AFTER TAIL SKID STRIKE OCCURS DURING TKOF PROC.

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I'M SETTING OUR TKOF AIRSPD BUGS. THE FO HAD INADVERTENTLY SET HIS ROTATE BUG 10 KTS SLOW. AS I WAS MONITORING THE TKOF ROLL AND JUST PRIOR TO MY CALLING 'ROTATE;' I NOTICED THE ACFT BEGIN TO ROTATE. I QUICKLY COMPARED MY BUG TO THE TKOF NUMBERS CARD TO SEE IF IT WAS RIGHT AS I CALLED 'ROTATE.' THE ROTATION RATE WAS SLOW AND THE AIRSPD WAS INCREASING NORMALLY SO I ANTICIPATED A NORMAL LIFTOFF EVEN THOUGH ROTATION WAS A LITTLE EARLY. DURING THE LIFTOFF I HEARD A SLIGHT SCRAPING SOUND BUT FELT NOTHING UNUSUAL. ACFT CTL WAS NORMAL THROUGHOUT THE TKOF AND ENSUING FLT. THE TAILSKID STRIKE WAS CAUSED BY A MIS-SET ROTATE BUG AND PERHAPS AIDED BY THE FACT THAT IT WAS A 5 DEG FLAP TKOF. MORE CARE NEEDS TO BE EXERCISED IN COMPARING THE BUG SETTINGS OF BOTH PLTS. I; FOR ONE; WILL BE MUCH MORE DILIGENT IN COMPARING MY BUG SETTINGS WITH THE FO'S IN THE FUTURE. SUPPLEMENTAL INFO FROM ACN 266891: DURING TKOF CHK ON A SCHEDULED FLT FROM DTW-BDL I CHALLENGED WITH 'MARKED BUG 155.' I NOTICED THAT BOTH CAPT AND FO HAD THE CORRECT MARKED BUG SET. I DID NOT NOTICE THAT THE FO'S V1/VR BUG WAS SET TO 129 INSTEAD OF 139 AS REQUIRED. SUPPLEMENTAL INFO FROM ACN 267014: ON TKOF FROM RWY 3C WHILE I WAS FLYING (FO); WE ROTATED EARLY AND HIT TAIL SKID. I HAD SET MY V1/VR BUG AT 129 KTS INSTEAD OF 139 KTS.