The National Transportation Safety Board has come to a conclusion on what could've caused the Calabassas helicopter crash that killed Kobe Bryant and eight other people, including his daughter, Gianna. The NTSB said that pilot Ara Zobayan suffered from an episode of "spatial disorientation." NTSB Chairman Robert Sumwalt said this is "the powerful, misleading sensations that can confuse a pilot conducting a visual flight who loses visual references, and what types of training can be effective in countering this effect."

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All nine people who were on the helicopter, including Pilot Ara Zobayan, died: Payton Chester, 13; Sarah Chester, 45; Alyssa Altobelli, 14; Keri Altobelli, 46; John Altobelli, 56; and Christina Mauser, 38. 

Zobayan served as the chief pilot on the Island Express Helicopters with over 10 years of experience flying over the site where the helicopter crashed. The craft didn't require two pilots but the previous owner of the Island Express Helicopter often made sure there were two sets of trained professionals operating it. "I think two pilots would increase the safety level. I flew with two pilots for a long time and in an airline environment, you get the redundancy that if one pilot is struggling, the other pilot would be able to sit back and say, 'Wait a minute, you are banking 30 degrees to the left and starting a descent," Chairman Michael Graham said.

Zobayan likely went against federal guidelines by flying into the fog, even after encountering iffy weather that morning. Graham said that the pilot should've dodged "adverse weather" and "divert, return to base or land the helicopter."