Pedro Torres, 19, of Pomona and the pilot, Matthew P. Shope, 18, of Los Angeles, died July 23, 2011 when their plane crashed in Corona.
The report on the crash released last week stated Torres was taking an introductory lesson from Shope after leaving Chino Airport that morning.
A witness stated she saw the airplane make an abrupt, swooping and descending left turn.
She desribed it as "extravagant" and similar to an aerobatic maneuver typically seen at air shows.
The witness also reported the airplane began to roll out of the turn sending the craft nose-first into the ground.
The impact was so violent that parts of the airplane were scattered for dozens of feet around the crash site and caused the wreckage to burst into flames.
Shope had been issued his private pilot certificate with a glider rating in November 2008.
He then received his commercial pilot certificate with ratings for airplane single-engine and instrument airplane on Jan. 24, 2011.
About four months before the fatal crash, he was issued his certified flight instructor certificate, records show. At the time, he applied for his instructor's certificate, Shope had logged about 350 flight hours.
Investigators determined it didn't appear there was anything mechanically wrong with the airplane.