Federal investigators have released dramatic video of the helicopter crash site where Philadelphia native and Lower Merion graduate Kobe Bryant, his daughter, Gianna, and seven others were killed, showing the magnitude of the scorched wreckage.

Mostly burned beyond recognition, the helicopter debris is scattered across 600 feet on the steep Calabasas, Calif., hillside, National Transportation Safety Board officials said Tuesday.

Flying Bryant and company from Orange County to his basketball camp in Thousand Oaks, Calif., Sunday morning, the Sikorsky S-76 chopper encountered extremely foggy weather, clearing the California mountain by “maybe 20 to 30 feet” before crashing in flames on the hillside and breaking apart upon impact, NTSB member Jennifer Homendy said.

Here’s what to know about the crash and ongoing investigation:

Helicopter lacked warning system: The aircraft, Homendy said Tuesday, lacked a terrain awareness warning system, which alerts pilots of when they are flying too close to the ground.

It’s still too early to know whether the lack of the terrain awareness technology, which Homendy said has been recommended by the NTSB since 2004, played a part in the crash.

Rapid ascent before crash: Moments before the helicopter slammed into the Calabasas hillside, the pilot, Ara Zobayan, rapidly ascended to avoid a cloud layer. The helicopter then barreled toward the ground at over 33 feet per second, “so we know that this was a high-energy impact crash,” Homendy told reporters.

Special clearance amid foggy conditions: Zobayan had years of experience and made the same trip in clear conditions just a day before the fatal crash, Homendy said. On Sunday, he was given special clearance to fly at under 1,000 feet in a fog so thick that it grounded the Los Angeles Police Department’s helicopters.

A former NTSB investigator told the New York Times that the helicopter’s rapid descent “could indicate that it had stalled before dropping to the ground, possibly because the pilot had tried to quickly pull up when he saw the approaching hill.”

A long investigation: Investigators will spend the next months determining what exactly led the helicopter carrying Bryant and his daughter to crash into the hillside.