What was found
FLT - 5553 - STL- COCKPIT AND CABIN FILLED WITH SMOKE WHEN PACK NR 1 WAS TURNED OFF DURING PUSH-BACK. MAINTENANCE DEFERRED APU BLEED SYSTEM.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
FLT - 5553 - STL- COCKPIT AND CABIN FILLED WITH SMOKE WHEN PACK NR 1 WAS TURNED OFF DURING PUSH-BACK. MAINTENANCE DEFERRED APU BLEED SYSTEM.