Investigators don’t know who was flying Greg Biffle’s plane when it crashed:

(NewsNation) — The National Transportation Safety Board provided updates on its investigation into a North Carolina plane crash that killed NASCAR legend Greg Biffle, his family and three others Thursday. The agency revealed it hasn’t been able to verify who was flying the plane when it crashed, and that three occupants had pilot’s licenses.

NTSB investigator in charge, Dan Baker, revealed the airplane took off at approximately 10:05 A.M. and was in the air for 10 minutes before the crash. Authorities are still unsure what specifically caused the crash; however, heavy drizzle was observed that morning.

Baker explained that preliminary data shows “the airplane made an initial left turn to the West, followed by another left turn back to the East towards the airport approximately 5 minutes after takeoff. The airplane then flew a left base turn to runway 28.”

The plane made initial impact with a runway light scansion and subsequently impacted trees, two other runway light stanchions and the airport runway fence. Witnesses say the aircraft came in very low.

NTSB member Michael Graham said a preliminary report of the accident is expected within 30 days, and a final report is expected in 12 to 18 months.

Investigators were able to locate the cockpit voice recorder and have sent it to Washington, D.C. for analysis.