A 20-year-old co-pilot who earned her pilot's license while still in high school was identified by her family as one of the nine people killed when a private jet crashed and burst into flames in South Florida on Sunday, according to reports.

The twin-engine business jet was en route from Austin, Texas, to the Bahamas when it suddenly went into a steep nosedive.

Flight-tracking data indicated the aircraft was descending at a rate exceeding 20,000 feet per minute before impact.