Gillespie remarked that no recovery of wreckage is contemplated.
"If wreckage is found, the imagery acquired on this expedition will be used to mount a subsequent recovery expedition equipped to safely retrieve and properly conserve whatever remains of the aircraft," he said.
He admits that there are several possible scenarios that could defeat TIGHAR's efforts to find the wreckage. For example, the plane could have floated away for miles before sinking, or it could have broken up, sunk close to the island and been buried by underwater landslides.
And of course, there is also the possibility that TIGHAR's hypothesis about Earhart's location proves incorrect.
"What would close the case, in a negative sense, would be the discovery of some presently unknown event or events that present a reasonable alternative explanation for all the various threads of evidence that point to the Earhart/Noonan flight ending at Nikumaroro," Gillespie told Discovery News.
"We're constantly looking for and debating possible alternative explanations. The strength of the case is in the abundance and diversity of the separate threads of investigation that all seem to point to the same conclusion," Gillespie said.
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