All the pieces of the helicopter wreckage needed for the investigation have been removed and are being transported to a secure location, in addition to evidence that includes an iPad, cellphone, maintenance records and other documentation.
The National Transportation Safety Board has finished its recovery work at the crash site and turned over the scene to local authorities.
"Did we locate all the significant components? Yes," said NTSB board member Jennifer Homendy. "That indicates to us, preliminary information is the helicopter was in one piece when it impacted the terrain."
The site remains closed to the public, and it is still a misdemeanor to attempt to access it, as hazardous materials such as fuel and magnesium need to be cleaned up, Sheriff Alex Villanueva said.
The NTSB expects to issue its first report on the crash in 10 days, but that will focus just on the facts it has determined and not the likely cause of the crash. The investigation into the cause could take 12 to 18 months, officials said.
Officials have determined that the Sikorsky S-76 helicopter crashed just 20 to 30 feet from the top of the hill in the Calabasas area Sunday morning, in an area located 1,085 feet above sea level. The area was a canyon with multiple hills of different elevations surrounding it.
Just prior to the crash, the helicopter was in a steep descent, estimated at 2,000 feet per minute, resulting in a "high-energy impact crash," NTSB officials said.
"This is a pretty steep descent at high speed," Homendy said. "It wouldn't be a normal landing speed."
Homendy also noted that her agency has in the past recommended safety improvements for helicopters such as this one after previous fatal crashes and those have not been implemented by the Federal Aviation Administration.
Those include requiring helicopters like this one to be equipped with a terrain awareness and warning system that would help the pilot see terrain in cloudy or foggy weather, and requiring the use of a flight data recorder and cockpit voice recorder.
The coroner's office also said through the use of fingerprints it has confirmed the identity of four of the nine people killed in the crash: John Altobelli, 56; Kobe Bryant, 41; Sarah Chester, 45; and Ara Zobayan, 50.
Those names had already been made public by family and friends, but this was the first official confirmation. Work continues to officially confirm the identity of the five others.
Sunday's crash also killed two coaches at schools in Orange County, the wife and daughter of one of those coaches, the pilot, and a mother and her daughter.
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Bryant's helicopter left Santa Ana in Orange County shortly after 9 a.m. and circled for a time just east of the 5 Freeway, near Glendale. Air traffic controllers noted poor visibility around Burbank, just to the north, and Van Nuys, to the northwest.
After holding up the helicopter for other aircraft, they cleared the Sikorsky S-76 to proceed north along the 5 Freeway through Burbank before turning west to follow the 101 Freeway.
Shortly after 9:40 a.m., the helicopter turned again, toward the southeast, and climbed to more than 2,000 feet. It then descended and crashed into the hillside at about 1,400 feet, according to data from Flightradar24. Data also revealed the chopper lost control about 15 seconds before impact.
The chopper went down in Calabasas, where Bryant's nearby Mamba Sports Academy in Thousand Oaks was holding a basketball tournament Sunday. Bryant and his young daughter were on their way to a travel basketball game along with another player and parent.
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The debris field is described as bigger than a football field, spanning an area of 500 to 600 feet. The impact crater is located on a hillside 1,085 feet above sea level. Pieces of the wreckage are on both sides of the hill.
The cause of the crash remains under investigation, but dense fog at the time was such that the Los Angeles Police Department and the county sheriff's department grounded their helicopters.
Justin Green, an aviation attorney in New York who flew helicopters in the Marine Corps, believes weather may have contributed to the crash. Pilots can become disoriented in bad weather, losing track of which direction is up. Green said a pilot flying an S-76 would be instrument-rated, meaning they could fly the helicopter without relying on visual cues from outside.
Los Angeles County Sheriff Alex Villanueva said his department's choppers would not have left their airport in Long Beach in such weather conditions.
But he noted that the department's choppers are smaller and less sophisticated in terms of electronics than the S-76.
Homendy said the restrictions that apply to the sheriff's department helicopters would not necessarily apply to the S-76.
"We have to look at this specific crash and this specific helicopter," she said. "We can't compare that to others."
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The NTSB confirmed that weather is one of several factors that investigators are examining. They are asking the public to send in any pictures they may have taken in the area of the crash that morning.
Weather pictures can be emailed to: firstname.lastname@example.org.
Homendy said the public has provided some pictures that have been helpful for the investigation, but there have also been photos sent of different areas of the country or even from around the world, and sifting through those slows down the investigation.
Among other things, federal transportation safety investigators will also look at the pilot's history, the chopper's maintenance records and the records of its owner and operator, Homendy said.
The helicopter did not carry a "black box" recording flight data and was not required to have one, Homendy said. But the pilot had an iPad that had some data, including a flight plan and weather briefings. Investigators may be able to examine other electronics from the aircraft for evidence.
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