A 75-year-old Hollister man who was on a riding lawnmower Thursday morning was struck and killed by a World War II-style "taildragger" airplane that was attempting to land at the private airfield along Frazier Lake Road in rural northern San Benito County.

Sheriff's deputies, firefighters and medics were dispatched to the scene at 10:29 a.m. Upon arrival at the Frazier Lake Airpark, they found the body of Douglas Ralph Jackson, who had been mowing the grass runway.

Sheriff's officials said the pilot did not see Jackson on the riding mower and struck him after all wheels had touched the ground. "The pilot comes in, thinks the runway is clear, and lands the plane," Sheriff's Capt. Eric Taylor told BenitoLink. "The front of the plane sits way higher than the back. He couldn't see over the cowling. At no point did he see the guy on the riding lawnmower."

The Federal Aviation Administration and the National Transportation Safety Board are investigating the cause of the crash. Neither weather nor mechanics seem to be a factor in the crash, officials said. Taylor told BenitoLink that the private airfield is "uncontrolled — there's not even a requirement for pilots to use a radio."

The pilot, from Monte Sereno, was en route from Reid-Hillview Airport in San Jose, to Frazier Lake, where he has a hangar. He sustained minor injuries to his head and arm and was treated and released at the scene.  He was cooperating with FAA and NTSB officials. His passenger sustained a large head laceration and was airlifted to an area trauma center. His condition was not known as of Thursday evening, officials said.

The FAA and NTSB will determine the cause of the crash.  As of this point, there are no criminal charges pending.