The Cessna 210 crashed Saturday afternoon in the Cedar Glen area of the San Bernardino Mountains, the Federal Aviation Administration said.
Doorbell camera captured the plane descending rapidly before it fell out of view and crashed.
The conditions of the pilot and passenger weren't immediately known, but they were alert and talking with responding firefighters, San Bernardino County sheriff's spokeswoman Cindy Bachman told the Sun newspaper.
The plane was heading from Chino to Big Bear City, according to FAA spokeswoman Elizabeth Cory. Air traffic control lost radio contact with the aircraft shortly before the crash, she said.
The FAA and National Transportation Safety Board will investigate the cause.
The Associated Press contributed to this report.