Officials looking for missing American adventurer Steve Fossett have scaled back their search effort after two weeks of hunting in the Nevada mountains have turned up no sign of him or his single-engine airplane.

Searchers using aircraft have scoured more than 25,000 square kilometers of rugged desert wilderness. They found several previously unrecorded airplane wrecks, but none were Fossett's.

Officials with the Civil Air Patrol -- a civilian Air Force auxiliary that conducts searches for missing aircraft -- said Monday they have done all they could. Airborne searching was halted, but two aircraft are on standby in case new clues came in.

Fossett's family, friends and fans are beginning to accept that he might have suffered a fatal crash somewhere in the trackless Nevada wilderness, and they are remembering his extraordinary life.

Steve Fossett loved a challenge. The legendary aviator spent most of his life making and breaking world records, not just in air travel, but in sailing and ballooning, as well. But Fossett did not see himself as a daredevil. He just thrived on the exhilaration of taking on - - and overcoming - - the impossible.

As he put it, he wasn't a stubborn man. If he realized that something just couldn't be done, or couldn't be done by him, he was willing to abandon his efforts. "But more often," he said, "I've found out that extremely difficult things, after you get involved in them, you find out that they are possible."

And Fossett wanted his achievements to be more than just record-setting exploits. While the adventure was important to him, he also wanted his projects to advance science. "It's important that we do something that improves the science of aeronautics, or [?] the science of weather," he explained during a 2006 appearance on VOA's Talk to America. "We want to make some contribution in that way."

Fossett is probably best known for his accomplishments in aviation. In 2005, he completed the first non-stop, solo flight around the world, without stopping to refuel. One year later, he broke the world record for distance, flying more than 26,000 miles [almost 42,000 km] in 76 hours.

But his proudest achievement may have been his 2002 world record for flying solo around the world in a balloon. When he started out, the longest that anyone had ever flow in a balloon was six days, and the longest distance was 5,200 miles [8,368 km].

"So to fly around the world," Fossett said, "we were going to have to nearly quadruple what had ever been done in a balloon before."

The attempt almost cost Fossett his life. He had made the journey half way around the world, when he flew into some thunderstorms.

"The balloon ruptured," said Fossett. "I was falling faster than what was survivable." But he knew he couldn't bail out, because if he did he would be, as he put it, "just out there floating in the water." In the last 30 seconds before he hit the water, Fossett cut away all the spare fuel tanks, giving what was left of his balloon just enough loft to slow it down, and allow him to survive the impact.

It took Fossett six tries in six years to finally complete the trip. In June of 2002, he flew his balloon more than 20,000 miles [32,000 km], traveling solo around the world in less than 15 days.

On Monday, September 3, at age 63, Steve Fossett took off in a small fixed-wing airplane, near Yerington, Nevada. He was looking for some good places to test out a modified jet racer, in which he planned to set a new land speed record.