After finding a half-dozen old airplane wrecks over 10 days, crews searching for missing aviator Steve Fossett focused on new tips about planes flying in the area the day his disappeared.

A Blackhawk helicopter and several ground crews were dispatched late Wednesday afternoon 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 fly out on Labor Day.

Search planes had flown the area several times, but the second sighting was reported to authorities Wednesday, so ground crews went in for a closer look, said Jeff Page, Lyon County's emergency manager. Searchers planned to return Thursday morning.

To the south, just across the California line, search planes flew over an area northeast of Yosemite National Park after a woman reported Wednesday 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, Page said.

A C-130 found nothing during a flyover Wednesday. California law officers planned to interview the woman Thursday.

More than a dozen aircraft scanned the terrain again Wednesday for any sign of Fossett, who took off Sept. 3 from a private airstrip about 80 miles southeast of Reno.

"We will continue until all credible leads are followed up. We don't know when that will be," Civil Air Patrol Maj. Ed Locke said.

The small air force combing the wilderness has spotted a half-dozen uncharted crash sites that might bring some solace to the families of fliers who disappeared decades ago.

William Ogle hopes some of the wreckage will be from the plane his father was flying when he vanished on a flight from Oakland, Calif., to Reno. He was only 5 at the time.

"I knew he had taken off in a plane and never came back," said Ogle, a professor of biomedical engineering at the University of Florida. "I can remember flying in his plane. He let me hold the controls, and I remember looking out the window."

Like Fossett, Charles "Chazzie" Ogle did not file a flight plan for the business trip, so searchers didn't know where to look in the vastness of the rural West in 1964, Ogle said.

Leaders of the search operation for Fossett say they have not had time to investigate the crash sites in detail because their top priority is finding the famous adventurer, not recovering old aircraft.

"When all is said and done, they'll send ground crews in to thoroughly investigate what is left," Civil Air Patrol Maj. Cynthia Ryan said of the old crashes.

Fossett survived a nearly 30,000-foot plunge in a crippled balloon, a dangerous swim through the frigid English Channel and hours stranded in shark-infested seas. But 10 days after he took off on a routine flight and never returned, there were many doubts about his survival.

The search covers 17,000 square miles — an area twice the size of New Jersey — stretching roughly from the Sierra Nevada ridge west of the Nevada-California line nearly 100 miles to the east.

Authorities have received nearly two dozen calls from people across the country saying they possibly had loved ones on one of the planes discovered this week.

Records are especially fuzzy on planes that disappeared many years ago. For example, there is no record of Chazzie Ogle's ill-fated flight at the Florida-based Air Force Rescue Coordination Center, which maintains a national registry of known sites of plane wrecks.

Ogle hopes Fossett's plane is found quickly.

"I don't want to see his family go through this," Ogle said. "It's better to know what happened. You have that uncertainty hanging over your life."