Here's what happened in the minutes before Kobe Bryant's helicopter crash

Minutes before the crash, their pilot was trying to get special permission to fly though foggy conditions.

Seconds before the crash that killed all nine people on board, the pilot told air traffic control he was trying to avoid a cloud layer. It was the last time anyone on the ground heard from him.

While federal investigators try to determine what caused the crash, excerpts of air traffic control recordings help build a timeline of what happened in the flight's final moments.

9:06 a.m. PT Sunday

The Sikorsky S-76B helicopter takes off from Orange County, California, according to the flight tracking site FlightRadar24.com.

The helicopter was headed from the southern Los Angeles area to the northern Los Angeles suburbs.

Bryant was supposed to coach a youth basketball team, the Lady Mambas, at their 12 p.m. game in Thousand Oaks, California. Gianna, 13, was on that team. Two other girls in the helicopter, Alyssa Altobelli and Payton Chester, were also on board.

Around 9:21 a.m. PT

The helicopter starts circling over Glendale, California, close to the city of Burbank.

"Helicopter 2EX, hold outside Burbank Class C airspace. I have an aircraft going around," an air traffic controller says.

Young athletes, a baseball coach and moms were among the crash victims

"2EX, holding," the pilot replies.

Air traffic control audio indicates the pilot, Ara Zobayan, had requested SVFR clearance, or special visual flight rules clearance.

SVFR clearance allows a pilot to fly in weather conditions worse than those allowed for regular visual flight rules. Sunday morning, the Los Angeles Police Department had grounded its helicopters because of low visibility from fog.

Pilots sometimes request SVFR clearance mid-flight if weather conditions suddenly change. Those granted permission typically keep closer contact with air traffic control.

Around 9:24 a.m. PT

An air traffic controller says "it's gonna be a little bit" before the pilot can continue.

"OK, we'll continue holding," Zobayan replies.

A National Transportation Safety Board member later said there was a delay because of traffic.

Around 9:33 a.m. PT

The helicopter heads north. Air traffic control tells the pilot to "follow the 5 Freeway" and maintain SVFR conditions.

The pilot confirms he heard the instructions: "Maintain special VFR at or below 2500, I-5 northbound."

Later, the Burbank air traffic controller tells the pilot to switch to Van Nuys air traffic control.

The pilot contacts the Van Nuys tower: "Van Nuys, Helicopter 2EX with you for the special VFR transition. We are currently at 1400."

The controller tells the pilot: "Wind calm, visibility 2 1/2 , ceiling 1100 overcast, Van Nuys altimeters 30.16. Cleared into Van Nuys Class D northeast of Van Nuys."

At one point, the pilot requested flight following, which is radar assistance for a flight that helps the pilot avoid traffic, NTSB member Jennifer Homendy said.

But air traffic control said the helicopter was too low to provide flight following assistance, Homendy said.

The pilot told air traffic control he was going to climb higher to avoid a cloud layer. It was his last transmission.