As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(B-18610) RTO DUE TO TAKEOFF WARNING SOUND. TAKEOFF WARNING HORN SOUNDED AFTER PUSHING TO/GA SWITCH, ACFT REJECTED TAKEOFF. SPEED BRAKE LEVER WAS FOUND NOT IN DOWN POSITION PROPERLY. THE GROUND SPEED WAS 10 KNOTS WHEN RTO. SPEED BRAKE WAS THEN FULLY PUSHED DOWN AND CONTINUED TO TAKEOFF WITH NO WARNING. RTO INSP FOUND NORMAL AFTER ACFT RETURNED TO DEPARTURE.