New questions are being asked about the helicopter crash in heavy clouds that killed NBA legend Kobe Bryant and eight other people after it emerged that the company that owned the helicopter is not legally certified to allow its pilots to fly in conditions of reduced visibility that requires pilots to use instruments, rather than their eyes.

Although pilot Ara Zobayan was trained and certified in flying using instruments only, and such instruments were available in the chopper, he did not have the legal authority to navigate with those instruments because Island Express Helicopters was not federally certified to operate flights using instruments only, The New York Times reports Friday, citing “three sources familiar with the charter helicopter company’s operations.”

Island Express, instead, had a Federal Aviation Administration operating certification that limited its pilots to flying under visual flight rules (VFR), which mandate at least three miles of visibility and a cloud ceiling no lower than 1,000 feet above the ground.

This is not usually an issue in sunny Southern California, and even local police helicopters don’t have instrument-flight certification, the paper says, but at the time of the crash, the area where the chopper came down was shrouded in clouds.

The new details about Island Express’s FAA certification may help explain why why the pilot “did not file an instrument flight plan that would have allowed him to climb well above the fog-shrouded hills and head to Camarillo Airport,” the Times reports.

No local charter companies maintain instrument flight certification, the Times reports, adding that such certification drastically increases training, equipment, and insurance costs.