Chicago ? The wife of adventurer Steve Fossett went to court Monday to have him found legally dead, saying she believes he perished when his plane disappeared over the Nevada desert in September.

Peggy Fossett asked a Cook County probate judge to begin the process of distributing his assets according to his will.

“(Steve) Fossett’s wealth is vast, surpassing eight figures in liquid assets, various entities and real estate,” the court petition said.

Fossett was reported missing Sept. 3 after he failed to return for a lunch appointment from what was supposed to be a pleasure trip while a guest at the ranch of Barron Hilton, the hotel magnate. Fossett had only one bottle of water with him.

“As anyone can imagine, this is a difficult day for our family,” Fossett’s wife, who lived in Chicago with her husband, said Monday in a written statement. “We will continue to grieve and heal, but after nearly three months we feel now that we must accept that Steve did not survive.”