What was found
ASH 7220 BNA TO DEN. RETURN TO GATE DUE TO LEFT AND RIGHT PACKS AUTO FAIL WITH VISIBLE SMOKE IN THE CABIN. OPERATED BOTH ENGINES, BOTH PACKS AND THE APU FOR APPROXIMATELY 20 MINUTES WITH NO DEFECTS NOTED.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
ASH 7220 BNA TO DEN. RETURN TO GATE DUE TO LEFT AND RIGHT PACKS AUTO FAIL WITH VISIBLE SMOKE IN THE CABIN. OPERATED BOTH ENGINES, BOTH PACKS AND THE APU FOR APPROXIMATELY 20 MINUTES WITH NO DEFECTS NOTED.