A plane with the same tail number as that flown by Mr. Fossett was discovered in several pieces strewn across a wide area in the Ansel Adams Wilderness section of Inyo National Forest, about 120 miles south of the Nevada ranch where he departed on Sept. 3, 2007, for what he had said would be a brief trip.

No human remains have been found, but 50 ground searchers were going into the region on Thursday with five dogs trained to sniff for cadavers, said Nancy Upham, a spokeswoman for the Inyo forest.

“Most of the plane was not intact at all,” Ms. Upham said. “The search crew was able to locate a number of pieces. The engine was found 300 feet from the main fuselage of the plane. The plane was pretty badly destroyed.”

A spokesman for the National Transportation Safety Board said in a statement that its chairman, Mark V. Rosenker, and investigators were heading to the remote airport in Mammoth Lakes, Calif., to confirm the findings.

The search for Mr. Fossett was renewed this week after a hiker, Preston Morrow, said he came across a few of Mr. Fossett’s belongings in some bushes in the Mammoth Lakes region on Monday. Among the items he found were Mr. Fossett’s Illinois-issued Federal Aviation Administration identification, his pilot’s license, a tattered sweatshirt and about $1,000 in cash. The discovery prompted officials from the Mono County and Madera County sheriff’s offices to retrace Mr. Morrow’s steps on foot and by air.

Mr. Fossett, 63, of Chicago, took off for what was expected to be a brief flight on Sept. 3, 2007, from a private ranch in Yerington, Nev., about 120 miles north of the high-mountain Sierra Nevada area where Mr. Morrow found the items. Mr. Fossett never returned, and the largest air and ground search in United States history, across a 17,000-square-mile region, failed to find him or his blue-and-white Bellanca Citabria Super Decathlon.

Earlier on Wednesday, Undersheriff Frank Bernard said searchers needed to hurry because the area where Mr. Morrow uncovered the items was expected to receive its first snowfall of the season this weekend. Mammoth Lakes is about 10,000 feet above sea level, and snow makes already difficult terrain largely impassable and could bury plane wreckage.

Mr. Morrow, a 43-year-old ski shop owner, told KNBC-TV in Los Angeles that he was hiking “way, way off” the established trails in the Ansel Adams Wilderness section of the two-million-acre Inyo National Forest when he first spotted a bunch of $100 bills. He then noticed the laminated cards with Mr. Fossett’s name but did not notify the authorities until Tuesday because it took him a day to recall who Mr. Fossett was, he told KNBC.

Mr. Fossett’s wife, Peggy, issued a statement on Wednesday saying she was monitoring the situation.

“I am hopeful that this search will locate the crash site and my husband’s remains,” Mrs. Fossett said. “I am grateful to all of those involved in this effort.”

The Fossetts were married for 39 years and had no children. Mr. Fossett was declared dead by a Chicago judge this year at his wife’s request.

The Inyo region was flown over repeatedly during the monthlong search for Mr. Fossett, but those who have hiked and flown over it say it is dense, mountainous forest where something as small as a two-seat light aircraft would be easy to overlook.

“It’s very hard to see by air; there’s so many crevices, so many rocks, so many crazy shapes that unless you’re looking literally a few feet from it, it would be very hard to see,” said Rusty Aimer, chief executive of Aviation Experts, an aviation consulting firm based in San Clemente, Calif., who has flown the Inyo region many times. “Everybody was saying that someday some hiker would run into the wreckage of his airplane, and here it is, that’s almost exactly what’s happened.9 D