As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 1275 - PIT-STL - AFTER ROTATION, BOTH AFT LAV SMOKE DETECTORS SOUNDED FOR ABOUT 3 MINUTES, THEN QUIT. RETURNED TO FIELD. CHECKED A/C FOR ANY PROBLEMS RELATED TO SMOKE. NONE NOTED. REPLACED BATTERIES IN BOTH SMOKE DETECTORS AND REPLACED BOTH WATER SEPARATOR BAGS. TAXIED A/C AND RAN BOTH ENGINES AT TAKEOFF POWER. ALL CHECKED NORMAL. RETURNED A/C TO SERVICE. (M)