Billionaire John Walton, the second son of Wal-Mart Stores founder Sam Walton died yesterday when a small plane he was piloting crashed shortly after take-off in Wyoming.
Mr Walton, an experienced pilot who was a resident of Jackson Hole, was flying a home-made aircraft, with an aluminum body, cloth-covered wings and a small engine.
It crashed onto a sagebrush-covered plain in Grand Teton national park. Park rangers were investigating the incident, a park spokeswoman said, adding that the Federal Aviation Administration had declined to do so as it involved an unregistered aircraft.
The cause of the crash has not yet been determined, Wal-Mart said in a statement.
Mr Walton (58), was ranked 11th on Forbesmagazine's most recent list of the world's richest people, with a net worth estimated at $18.2 billion.
He served in the US Army Green Berets as a medic during the Vietnam War. He was awarded a Silver Star for helping save the lives of several members of his unit while under intense enemy fire.
Throughout his life, Mr Walton pursued a variety of business interests, including crop dusting in the 1970s and boat building in the 1980s and 1990s. He was also a keen philanthropist.
His brother S. Robson Walton is chairman of Wal-Mart's board.