FACTBOX | What we know about Malaysia’s missing MH370 plane, as fresh search to start 11 years after disappearance

Underwater searches

Malaysia, Australia and China launched an underwater search in a 120,000-square-kilometre (46,332-square-mile) area in the southern Indian Ocean, based on data of automatic connections between an Inmarsat satellite and the plane.

The search, which cost about AU$200 million ($131.54 million), was called off after two years in January 2017, with no traces of the plane found.

In 2018, Malaysia accepted a "no-cure, no-fee" offer from US exploration firm Ocean Infinity for a three-month search, meaning the company would only get paid if it found the plane.

That search covered 112,000 square kilometres (43,243 square miles) north of the original target area and also proved fruitless, ending in May 2018.