Kobe Bryant's pilot was warned he was flying "too low" just seconds before the helicopter crashed, killing all nine onboard.
The US National Transportation Safety Board (NTSB) has launched a "go team" of up to 18 investigators into the crash that killed the basketball legend amid questions about why the helicopter was flying low in foggy conditions.
Investigators will focus on bad weather and mechanical problems as a potential cause of the tragic crash that has been mourned by basketball fans around the world. Why the helicopter was flying in conditions so foggy that even LA police had grounded their choppers will also likely be raised.
Detailed analysis of the flightplan of Bryant's Sikorsky S-76B helicopter, built in 1991, showed it took off just after 9am from John Wayne Airport in Orange County and tracked north over Los Angeles before tacking left towards Thousand Oaks where Bryant's Mamba Sports Centre is based.
Audio from air traffic control reveals the experienced pilot, named as Ara Zobayan, was warned "you're too low" seconds before the helicopter disappeared from radar.
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What exactly happened in the minutes leading up to the crash is unclear, however flightplan analysis published by New York Magazine shows the pilot was flying above hilly terrain and in thick fog, and using "visual flight rules" - or VFR - which means relying on sight rather than instruments to fly.
New York City University aviation professor Paul Cline stressed while he had no direct knowledge of Bryant's incident, fog can quickly turn dangerous when pilots become disorientated.
When you get in the soup, your senses don't work," he said. "For me, I always feel like I'm falling to the right. Other people might feel like they're falling to the left, or climbing."
The helicopter eventually came down on a steep hillside in Calabasas, sparking a small bushfire.
SHERIFF'S HEARTFELT REQUEST
Police and firefighters were first on the scene and quickly established a containment area, according to LA sheriff Alex Villanueva, who has handed the fatal investigation to the NTSB.
Mr Villanueva said the NTSB was expected to arrive on the scene on Sunday night, but warned its "extensive investigation" would likely take "a great deal of time".
"It's a logistical nightmare in a sense because the crash site itself is not easily accessible," he said, adding a heartfelt request for those trying to get close to the site.
"However, we are now faced with wellwishers and people mourning who have descended on the area, on the residential community, and even the crash site itself.
"We have to reiterate it is off limits to everybody except the first responders and investigators."
Mr Villanueva warned all those attempting to access the site would be asked to present photo ID.
LA TIMES PRODUCES MOVING TRIBUTE
Tributes have been flowing across the world for Bryant, his 13-year-old daughter Gianna, and the seven others who perished in the crash.
While police have not yet officially named the victims, friends and family members have confirmed each of their deaths online.
They include John Altobelli, his wife Keri and youngest daughter Alyssa, who played on the same basketball team as Gianna.
Another member of the team, Payton Chester, and her mother Sarah also died, along with Christina Mauser, who coached girls basketball at a nearby private school.
The helicopter pilot, Ara Zobayan, was the final victim and a much loved member of the aviation community, according to friends.
On Tuesday, the Los Angeles Times ran a sombre photo of Bryant on its frontpage, farewelling the star who "loved" his city.
"He joined the Lakers when he was 17. At 25, he faced a sexual assault charge that threatened his marriage, career and reputation. But by the time he retired, he had won five NBA championships," it wrote.
"He was the NBA Finals MVP twice and league MVP once. We won two Olympic gold medals. He scored 81 points in one game. The Lakers retired not one, but two of his numbers.
"He founded Granity Studios and won an Academy Award. He became known as the devoted father of four daughters. He loved a city that loved him back. Kobe Bryant is dead at age 41."
The back page of the paper featured another touching photo of Bryant with his daughter Gigi on his shoulders.