Finding the wreckage and the plane's flight data and cockpit voice recorders is a major challenge.
It took two years to find the black box from Air France Flight 447, which went down in the Atlantic Ocean on a flight from Rio de Janeiro to Paris in 2009, and searchers knew within days where that crash site was.
The Malaysian government statement said it was sending a team to Perth to assist with the search operation, but it did not give details.
The batteries on the recorders' “pingers” are designed to last 30 days.
After that, the pings begin to fade in the same way that a flashlight with failing batteries begins to dim, said Chuck Schofield of Dukane Seacom Inc., a company that has provided Malaysia Airlines with pingers in the past.
Schofield said the fading pings might last five days before the battery dies.
Once a general area is pinpointed for the wreckage, experts say salvagers will have to deal with ocean depths ranging from 3,000 to 4,500 meters (10,000 to 15,000 feet).
