John Morgan flies his plane Wednesday in Minden, Nev. Morgan is one of many searching the area for missing aviator Steve Fossett. After finding a half-dozen old airplane wrecks, crews searching for Fossett focused on new tips about planes actually flying in the area the day his disappeared.

Reno, Nev. ? Authorities investigating the disappearance of millionaire adventurer Steve Fossett said Thursday that they’ve ruled out some of the more unlikely explanations for why they haven’t found his plane, including the possibility he wanted to vanish.

No trace has been found of his single-engine plane despite a small air force that has scoured the canyons and hillsides along the Sierra Nevada’s eastern front for 11 days, raising the prospect that he’s just not there.

Rich, famous and apparently happy in his pursuits of adventure, Fossett had been flying on a scouting mission for a dry lake bed to attempt to break the land speed record.

Could he have grown tired of the limelight and wanted to start a new life? Could he have fled some personal or financial problems?

“We have looked at that,” Lyon County Undersheriff Joe Sanford told The Associated Press on Thursday.

“We have assets that are tracking financial records, credit card transactions, cell phone use,” he said, noting they have not received any calls claiming sightings of Fossett.

“With his notoriety, we believe he couldn’t walk away from this type of event,” he said. “People would recognize him.”

No foul play suspected

Investigators also dismiss the notion that Fossett met foul play or was kidnapped to be held for ransom.

“If we find a wreck area, we will need to treat that like a crime scene before we rule out foul play,” Nevada Highway Patrol Trooper Chuck Allen said. “But there’s no reason to think about that now.”

A longtime prosecutor in neighboring Washoe County said the normal course of an investigation would include at least a brief look into even the most unlikely scenarios.

“I have no idea about Mr. Fossett, but I know that it has happened in the past where we have had guys just disappear and stage things,” Washoe County District Attorney Richard Gammick said.

“When you can’t find individuals for an extended period of time, you would have to look at everything,” Gammick said.

But Gammick thinks it’s much more likely that Fossett’s plane simply went down in a rugged canyon, or perhaps a lake, where searchers haven’t found him and perhaps never will.

‘No new major leads’

High winds kept most search planes grounded Thursday. Ground crews returned to a spot in the Pinenut Mountains in western Nevada where two witnesses reported seeing a plane like Fossett’s fly into a canyon, but not out, on Labor Day. About 80 percent of the area has been searched, Civil Air Patrol Maj. Ed Locke said.

“There are no new major leads today,” Sanford said late Thursday afternoon.

To the south, just across the California line, crews finished searching an area northeast of Yosemite National Park. California law officers met Thursday with a woman who reported a day earlier that she had camped there over Labor Day and had heard a noise that sounded like an airplane, followed by what sounded like an explosion. A plane found nothing during a flyover Wednesday.

“They did a pretty good extensive search … and they didn’t come up with anything,” Alpine County Sheriff John Crawford said.

Crash sites were recorded

Another possibility is that Fossett strayed much farther afield than the search area, which already covers 17,000 square miles. The plane he was flying could have taken him deep into neighboring California, Oregon or Arizona, all states with vast areas of wilderness.

“We may never find it, that’s an absolute fact,” Locke said. “But we’ve got to continue as long as we’ve got leads.”

Locke also said Thursday that old plane wreck sites found last week that were thought not to have been previously charted actually had been.