Narrative:

We started the APU 15 minutes before push back. Approximately one minute later the cockpit and cabin began to fill with smoke. We immediately shut down both packs; the recirculation fans; and the APU. The smoke dissipated quickly. We called station maintenance; dispatch; and maintenance control. Station maintenance wanted to trouble shoot the problem; but we decided to deplane the passengers before troubleshooting. It was determined that the problem was APU oil entering the pneumatic system. The APU was deferred. Dispatch and maintenance control were consulted and we were dispatched with release 02. After a ground air start at the gate and a cross bleed start after pushback we began the after start checklist and the air conditioning smoke returned along with the flight crew rest smoke alarm. We immediately shut down both packs and both engine bleeds and returned to the gate. Maintenance; station; and dispatch were notified of our status and the flight was cancelled.

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Original NASA ASRS Text

Title: During preflight a B777 flight crew shut down the APU; pneumatic system and the packs when the cabin filled with smoke shortly after the APU was started. After Maintenance investigated and deferred the APU due to its oil entering the pneumatic system the flight was boarded and began taxi. Shortly thereafter; the smoke returned to the cabin; the shutdown procedures were repeated and the aircraft returned to the gate where the flight was canceled.

Narrative: We started the APU 15 minutes before push back. Approximately one minute later the cockpit and cabin began to fill with smoke. We immediately shut down both packs; the recirculation fans; and the APU. The smoke dissipated quickly. We called station maintenance; dispatch; and Maintenance Control. Station maintenance wanted to trouble shoot the problem; but we decided to deplane the passengers before troubleshooting. It was determined that the problem was APU oil entering the pneumatic system. The APU was deferred. Dispatch and Maintenance Control were consulted and we were dispatched with release 02. After a ground air start at the gate and a cross bleed start after pushback we began the after start checklist and the air conditioning smoke returned along with the flight crew rest smoke alarm. We immediately shut down both packs and both engine bleeds and returned to the gate. Maintenance; station; and dispatch were notified of our status and the flight was cancelled.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.