What was found
TAKEOF WARNING HORN SOUNDED AFTER ADVANCING THRUST FOR TAKEOFF. REJECTED TAKEOFF PER S.O.P. A/C WEIGHT 206200, IAS 0, OAT CEL 10, PRESS ALTITUDE 833, BRAKE ENERGY ZONE NORMAL FOUND BUILDUP OF DEBRIS ON FLAP/SWITCH FOLLOWUP CAM. CLEANED AND OPS CHECKED FLAP TAKEOFF WARNING SYS, OK IAW DC-8 MM 27-52-1. BRAKE ENERGY AND RTO NOTED BY MX.