NTSB releases preliminary report into deadly news helicopter crash in Chatsworth

CHATSWORTH, Calif. (NBC, KYMA) - The National Transportation Safety Board (NTSB) has released its preliminary report into the deadly NewsChopper4 helicopter crash in Chatsworth.

The NTSB said the helicopter was flying about 800-feet above ground while covering a fatal Metro bus crash on September 15.

In the final 29 seconds of the flight, the live video recording captured changes in helicopter noise, along with intermittent and continuous horns consistent with high and low main-rotor RPM warnings.

The Eurocopter AS-350B2 was equipped with warning systems designed to alert the pilot when engine or rotor speeds move outside safe ranges.

The NTSB is collecting video from people at the scene and interviewing witnesses.

Investigators have also moved the wreckage to a secure facility in Arizona for further examination.

The agency said the preliminary report contains no conclusions about what caused the crash, and a final report could take months or years.