(CBS News) A team of researchers will leave Hawaii Tuesday headed to a tiny island in the Pacific Ocean in search of Amelia Earhart's aircraft. They say they have evidence that Earhart and her navigator Freed Noonan managed to land their Lockheed Electra safely there, but died as castaways.
Seventy-five years ago Monday, one of this country's great mysteries began as Americans learned that Earhart was missing. The famous pilot's plane was last seen over the Pacific.
For her to vanish without a trace at the height of all that fame was then, and is now, inconceivable to some. Part-time horseman, full-time missing airplane detective Ric Gillespie founded the International Group for Historic Aircraft Recovery. Twenty-five years of research finally turned up a long forgotten photo, that he says, may show the holy grail in the Earhart puzzle - a piece of the aviator's plane.
"The components of this image match the shape and dimensions of elements in the landing gear of a Lockheed Electra," Gillespie said. The picture was taken in 1937 off Gardner Island -- now called Nikumaroro -- but that was some 300 miles to the southeast - of her intended target - Howland Island -- both needles in a floating haystack.
Earhart's mysterious disappearance was the stuff of Hollywood. But to Dorothy Cochrane, a curator at the National Air and Space Museum, there's no mystery. She says ran out of gas, and drowned.
"I believe that she went down somewhere to the northwest of Howland Island," Cochrane said. "I think they were fairly close unfortunately."
But Gillespie thinks in her effort to find Howland Island, Earhart stumbled on Nikumaroro instead -- and managed to make an emergency landing and then waited for help that never came.
Proof Earhart survived he says - came in weak radio signals heard after her disappearance.
While many were cruel hoaxes, but he says a teenager named Betty Klenck was so convinced that she heard Earhart's distress calls -- that she wrote it all down in her journal. She's now 91 years old and still swears it was Earhart's voice.
There's other evidence too, although he admits it's all circumstantial. Fragments of bones, and the heel of a woman's shoe were both found on Nikumororo in 1940. Years later Gillespie went back to that site and found more: bottles of hand lotion, freckle ointment dating from the 1930s, and even a zipper from what could be a flight suit.
"It tells a story," Gillespe said. "It tells a story of an American woman of the 1930s who's trying and who has failed to survive on that island."
"The artifacts that he's found are collateral pieces of civilization," Cochrane said. "Nothing that can be directly tied to Amelia."
This week Gillespie and his team will use side-scan sonar and underwater robots to look for what, if anything is left of Earhart's plane -- including that landing gear, if indeed that's what was in the picture in the first place.
"This is the biggest thing we've ever done," Gillespe said. We'll either find something or we won't."
It won't change what Earhart accomplished - but it could finally put her to rest.
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