AAIB Bulletin: 12/2017 N276AY EW/C2016/06/02 On 26 June 2016, thick white smoke suddenly appeared in the cabin of a fully loaded Airbus A330-300 prior to engine start with the door used for boarding still connected to the air bridge. An emergency evacuation initiated by cabin crew was accomplished without injury although amidst some confusion due to a brief conflict between flight crew and cabin crew instructions. The Investigation found that the smoke had been caused when an APU seal failed and hot oil entered the bleed air supply and pyrolysed. Safety Recommendations in respect of both crew communication and procedures and APU auto-shutdown were made.