From CNN:
Wal-Mart heir John Walton died Monday when his ultralight aircraft crashed after taking off from an airport in Jackson, Wyoming, the company announced. Walton, 58, served in Vietnam as a combat medic and was on the board of the Walton Family Foundation, the family's philanthropic enterprise. He was the second son of Wal-Mart founder Sam Walton and was ranked No. 7 on the Forbes magazine list of the 400 wealthiest Americans in 2004.