LOS ANGELES -- Wreckage from the helicopter that crashed last month and killed Lakers legend Kobe Bryant, his daughter and seven others did not show any outward evidence of engine failure, the National Transportation Safety Board said Friday.

Bryant, his 13-year-old daughter, Gianna, and the others died in the Jan. 26 crash in Calabasas, California. The group was flying to a girls' basketball tournament at his Mamba Sports Academy. Gianna's team was coached by Bryant and was playing in the tournament.

The NTSB is investigating the accident, including any role that heavy fog played, and a final report isn't expected for at least a year.

A witness told the NTSB the hillside where the crash occurred was shrouded in mist when he heard the helicopter approaching. It sounded normal, and he then saw the blue-and-white aircraft emerge from the fog moving forward and down. Within two seconds, it slammed into the hillside just below him.

Investigators said the twin-engine Sikorsky S-76B was traveling at more than 180 mph and 4,000 feet per minute when it crashed. The helicopter's instrument panel was destroyed in the crash and most of the devices were displaced, according to the NTSB's investigative update. The flight controls were broken and suffered fire damage.

Investigators believe that since a tree branch at the crash site was cut, it appears the engines were working and rotors turning at the time of impact. All four of the helicopter's blades had similar damage, the report said.

Friday's report was merely informational and did not offer any specifics about what caused the crash. The victims' deaths have been ruled an accident by blunt trauma, according to the Los Angeles County coroner.

The deaths shook Los Angeles and the sporting world, with memorials spanning the city and tributes at the Super Bowl and other games. A public memorial for Bryant and the other victims is scheduled for Feb. 24 at Staples Center.

The arena is where Bryant starred for the Lakers for most of his two-decade career, and the date 2/24 corresponds with the No. 24 jersey he wore and the No. 2 worn by Gianna.

Ara Zobayan was the chief pilot for Island Express Helicopters and had more than 8,200 hours of flight time. He was certified to fly solely using instruments -- a more difficult rating to attain that allows pilots to fly at night and through clouds -- and was a pilot to other celebrities, including Kawhi Leonard and Kylie Jenner.

The aircraft did not have a device called the terrain awareness and warning system that signals when an aircraft is in danger of hitting the ground. The NTSB has recommended the system be mandatory for helicopters, but the Federal Aviation Administration requires it only for air ambulances. U.S. Sen. Dianne Feinstein and U.S. Rep. Brad Sherman, both California Democrats, have called for the FAA to mandate the devices in the wake of the tragedy.

It's not clear if the warning system would have averted the crash. The helicopter was also not required to have a black box.

A public memorial for Orange Coast College baseball coach John Altobelli, his wife, Keri, and daughter Alyssa will be held Feb. 10 at Angel Stadium of Anaheim. Also killed in the crash were Bryant friends Christina Mauser, Sarah Chester and her daughter Payton.