John Walton, the son of Wal-Mart founder Sam Walton, has died in a plane crash.

Walton was piloting an ultralight plane that crashed shortly after take off from Jackson Hole airport in Grand Teton National Park, US, the retail giant said. He was pronounced dead at the scene.

Earlier this year Forbes magazine listed Walton as the 11th richest person in the world, with a net worth $18.2bn.