ANN ARBOR, MICHIGAN – Investigators are still trying to solve many questions behind a plane crash in Ontario that involved a University of Michigan student who is currently listed as missing. Xin Rong, 27, a doctoral student from China studying artificial intelligence, is a certified pilot who flew out of Ann Arbor March 15 with Harbor Springs as his charted destination, investigators said. After authorities were notified that the rented plane was long overdue for its return, they discovered the crash site in a forest near Manitouwadge, Ontario, just before midnight. Investigators from the Transportation Safety Board of Canada did not find a body in the plane. There were no footprints in the snow near the plane, and the passenger-side door was found unlatched.