A B-757 STRUCK ITS TAIL ON TKOF.

Narrative

ACFT 757; WT 168800 LBS; NORMAL V SPDS; MAX TKOF THRUST FLAPS 15 TKOF. TKOF USING THE SPECIAL NOISE ABATEMENT DEP. NORMAL TKOF BRIEFING FOR THIS ARPT AND ITS SPECIAL NOISE ABATEMENT PROC. TKOF ROLL WAS NORMAL WITH ALL SOD CALLOUTS; ROTATION AT VR. JUST AS THE MAIN GEAR LEFT THE RWY! A NOISE; WHICH SOUNDED LIKE A THUD; WAS HEARD. WE CONTINUED WITH THE DEP WITH ALL INDICATIONS NORMAL. UPON REACHING A SAFE DISTANCE AND ALT CLR OF ALL TFC. WE TRIED TO DETERMINE THE CAUSE OF THE NOISE. THE FLT ATTENDANTS WERE QUESTIONED WITH REGARDS TO THE NOISE; THEY SAID THEY HEARD A THUMP; BUT A SCRAPING NOISE WAS NOT HEARD. AS WE PROCEEDED ON COURSE; WE CONTACTED RAMP CTL TO SEE WHAT KIND OF CARGO WE HAD IN THE REAR CARGO AREA; THINKING IT MIGHT HAVE BEEN CARGO SHIFTING WHICH CAUSED THE NOISE. IT WASN'T CARGO THE RAMP INDICATED. AT THE TIME; DISPATCH NOTIFIED US THAT THE TWR INDICATED WE MIGHT HAVE HAD A TAIL STRIKE ON TKOF. THE TWR DID NOT INDICATE THIS PRIOR TO SWITCHING FREQS. UPON LNDG AND INSPECTION; WE HAD STRUCK THE TAIL ON THE APU DOORS. THE TKOF WAS NORMAL; THE ROTATION SEEMED NORMAL FOR THIS DEP.