They appeared to be operating at the time of the crash.

Witnesses hearing a normal sounding helicopter.

According to the NTSB report, Bryant, his daughter and friends heading to a basketball game along with the pilot.

All nine died in the fiery crash.

In that bad weather, the pilot decided to follow a highway toward their destination.

But is the chopper approach?

Calabasas?

The fog was thick, the pilot telling controllers he was going to climb above the trouble.

The helicopter does climb but starts turning left. 00:00:58.390 --> 00:01:0.620 Then suddenly, Ah, quick descent. 00:01:0.720 --> 00:01:6.540 More than 180 miles an hour as it continues, that left turn crashing into the hillside. 00:01:6.660 --> 00:01:12.120 Ah, witness on the hill saw the chopper pop out of the fog and says it was rolling left.

Was it because the pilot was disoriented?

Didn't know which way was up?

Or was there a mechanical malfunction that caused a loss of control and doomed the helicopter?

So let's get to David Curly.

He covers Aviation Flores and David.

I know.

There were also clues at the crash site that the engines and rotors were actually working.

Investigators say that they found it hit a tree before the ground.

The rotors slicing through a three inch branch means the blades were turning before the crash.

David and we've also learned that this is going to take about a year to finish this investigation.

Kobe Bryant and the others will be memorialized on the 24th of this month in Los Angeles.

David didn't curly on the investigation again tonight, David.

Thank you.

Hi, everyone.

George Stephanopoulos here.

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