The helicopter that crashed, killing basketball great Kobe Bryant, his daughter and seven others, was not certified to fly in foggy conditions.
According to officials, Island Express Helicopters, which owned the Sikorsky S-76B that crashed, was allowed to operate under visual flight rules.
"The preliminary information is Island Express' 135 certificate did not allow for IFR flight," said Keith Holloway, a National Transportation Safety Board spokesman. "No other specifics are available at this time."
Preliminary investigations have pegged foggy weather conditions as a possible cause for the crash.
Meanwhile, the Lakers played their first game since Bryant's death, and paid tribute to the star by wearing his numbers - 8 and 24 - during warm-up. They went against the Portland Trail Blazers at the Staples Center in LA.
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