An elderly passenger in a light plane tried to grab the aircraft's controls before the pilot was forced to make an emergency landing in a paddock in central western NSW, the pilot has told police.

The 23-year-old pilot had to restrain his 82-year-old passenger before landing the Beechcraft Duchess aircraft in a paddock off Titania Road in Oberon just before 3pm on Monday.

Acting Inspector Gareth Smith said the elderly man had booked the flight from Bankstown to Cowra for a business trip, but mid way through the flight started acting erratically.

"The pilot said that he started grabbing the controls, turning off fuel lines, and turning buttons randomly on and off," Acting Inspector Gareth Smith said.