SYDNEY - Searchers racing to find flight MH370's "black box" face daunting hurdles ranging from undersea volcanoes to mountainous seas as they operate in one of Earth's most remote locations, experts said Wednesday.
They warned there was no guarantee that an unprecedented international search operation involving the militaries of six nations would succeed in retrieving wreckage of the doomed Malaysian Airlines plane which disappeared on March 8 with 239 people on board.
Australian Prime Minister Tony Abbott on Wednesday said the search zone -- in the southern Indian Ocean some 2,500 kilometres (1,550 miles) southwest of Perth -- was "as close to nowhere as it's possible to be".
University of New South Wales oceanographer Erik van Sebille said the crash site was in an area known as "the Roaring Forties", notorious among mariners for its hostile seas.
"In general, this is the windiest and waviest part of the ocean," he said. "In winter, if a storm passes by you can expect waves of 10-15 metres."
The Soufan Group, a US-based strategic security intelligence consultancy, likened searching for debris in such conditions to "finding a drifting needle in a chaotic, colour-changing, perception-shifting, motion-sickness-inducing haystack".
"A random wave might obscure the object when the eyes pass over it; sun glare off the water may blind momentarily; a look two degrees to the left when the object is most visible may cause the moment to pass," it said.