Seconds before the crash that killed all nine people on board , the pilot told air traffic control he was trying to avoid a cloud layer . While federal investigators try to determine what caused the crash, excerpts of air traffic control recordings help build a timeline of what happened in the flight's final moments. Around 9:21 a.m. PTThe helicopter starts circling over Glendale, California, close to the city of Burbank. The pilot contacts the Van Nuys tower: "Van Nuys, Helicopter 2EX with you for the special VFR transition. Cleared into Van Nuys Class D northeast of Van Nuys."

Source: CNN January 29, 2020 00:11 UTC