1.   Donohue, who has a doctorate in aerospace engineering from Oklahoma State University, is licensed to fly single-engine planes.

2.   He also was an avid pilot licensed to fly all types of aircraft, including commercial airliners, helicopters and hot air balloons.

3.   In many other countries night flights are restricted to pilots licensed to fly by instruments alone.

4.   Still, Kennedy was not licensed to fly using instruments alone.

5.   Nikolian was not licensed to fly without a trainer, Malek said.

6.   Yates also had a career in the U.S. Army and was a commercial pilot licensed to fly transport planes or helicopters, Army and Federal Aviation Administration records show.