As the search for Steve Fossett dragged into its ninth day Tuesday, experts said they doubted the millionaire adventurer could have survived more than a week in the rugged desert since his plane vanished.

While the resourceful aviator could scratch water, food and shelter from the desolate Nevada landscape, experts said his first order of business would have been signaling rescuers.

“There’s no news of him signaling for help and that’s a problem,” said David McMullen of Berkeley, Calif., a leader of the hiking group Desert Survivors, whose members frequently venture into some of the country’s harshest terrain. “He’s either so injured he can’t signal or he’s perished.”

Fossett’s plane was equipped with an emergency beacon, and he was wearing a high-tech watch capable of generating a similar signal. Searchers have received no signal from either device, and haven’t spotted a lower-tech distress signal such as a fire or massive X made of rocks or sticks.