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Fossett search still 'trying to track down all leads'

MINDEN, NV. –  In rugged terrain 90 miles southeast of Reno, a group of searchers listened to a radio for faint signs of life on Tuesday night. Was it a distress signal from aviator Steve Fossett

Over the last two days rescuers occasionally heard a radio transmission of a recorded human voice, a "ghost ELT," Emergency Location Transmitter, is how they described it. They sent up a helicopter to try to trace the radio, but the signals were sporadic and only last a few seconds.

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"We do not believe it's accurate," said Joe Sanford, the Lyon County Under-Sheriff, "but we are trying to track down all leads."

Sanford says the radio voice says, "niner-niner-four-one-one," on a radio frequency reserved for emergency signals from aircraft. The numbers bear no apparent relation to Fossett, or to the plane he was flying eight days ago, which only deepens the mystery.

If the number was a reference to the tail number of an airplane, it traces to a plane based in Illinois, which authorities say is safe at its home base, "in the hangar."

Searchers confess they are "at a loss" for an explanation. They have traced two other ELT signals in the area to planes which are accounted for at nearby airports.

With the search dragging into its second week, some survival experts have begun to doubt that the adventurer could have survived in the harsh desert conditions for so long. 

A ground crew still spent yet another night in tents and sleeping bags on Tuesday evening – hoping to intercept the radio voice and find it's origin in the rough Nevada back country. By Wednesday morning, they called off the ground search for the "ghost signal." The crew said that they had "exhausted all possiblities" there.

But the air search continued on Wednesday, with about 20 aircraft taking off around 10 a.m. local time hoping to find the adventurer in the rough Nevada back country.