The search for missing millionaire adventurer Steve Fossett in the rugged and remote high Nevada desert was cut back on Monday.

The Civil Air Patrol, which had 20 planes and 60 searchers aloft over the weekend, suspended further flights and left two planes and a small team on standby at the airport here.

"We don't like to do that. It's against our nature to walk away from a search," Maj. Cynthia Ryan of the Nevada CAP said. "But at some point you have diminishing returns."

Ryan said volunteer CAP pilots in up to 28 planes made 245 flights searching for Fossett, 63, who disappeared on Labor Day while flying his plane. The search has covered an area twice the size of New Jersey.

The National Guard kept five helicopters on search duty — and many private aircraft continue to operate out of hotel mogul Barron Hilton's 1 million-acre Flying M Ranch, where Fossett had been staying.

Search and rescue crews on the ground also continued their efforts as the search for Fossett entered its third week.

Maj. Ed Locke of the Nevada Air National Guard said the guard's helicopters will continue flying and will be able to hover closer to the ground than the CAP planes. He said tips have dropped off.

Lyon County Sheriff Allen Veil, whose county includes Hilton's ranch, said he's observed the private search and has seen "a sense of optimism that Mr. Fossett is still out there alive, and they're set on finding him."

But the sheriff also said it's possible that the organized search for Fossett might turn up nothing and some hiker or hunter eventually will come across the wreckage of Fossett's single-engine plane.

As the search continued on the edge of the Sierra in northern Nevada and eastern California, comparisons were being made to the mystery of Amelia Earhart's disappearance over the Pacific Ocean 70 years ago.

Ric Gillespie, leader of an effort this summer to find Earhart, who vanished in July 1937 during an around-the-world flight attempt, said the comparisons will continue to grow.

"We like to think that anything is findable with enough resources. But it could turn into another Amelia Earhart situation," said Gillespie, head of The International Group for Historic Aircraft Recovery, on Sunday.

"If they don't find something, the mystery element will grow and grow," he said.