The pilot of a terrifying flight from Australia to New Zealand told those on board he temporarily lost control of his Boeing 787 after one of its instruments failed, a passenger said Monday, as authorities investigate what caused a sudden drop that threw travelers around the cabin, injuring dozens.

In accordance with rules outlined by the International Civil Aviation Organization (ICAO), Chile’s Directorate General of Civil Aeronautics (DGAC) have sent investigators from the agency’s Operations and Airworthiness team to look into the incident, according to a statement released on Tuesday.

“Given that the State of Registration of the aircraft involved is Chilean, it has been established with the New Zealand Transport Accident Investigation Commission (TAIC) that the investigation will be carried out by the Chilean Aeronautical Authority,” the statement read.

The incident aboard LATAM Airlines flight 800 from Sydney to Auckland is the latest to hit troubled aircraft manufacturer Boeing, which has been rocked by years of quality and safety issues.

Passenger Brian Jokat described the horrifying moment when he was woken from his sleep as the aircraft “dropped something to the effect of 500 feet instantly.”

“That’s when I opened my eyes and there was various individuals at the top of the plane. Just stuck to the roof and then they fell to the floor. And then I just realized I’m not in a movie, this is actually for real,” he told CNN’s Erin Burnett.