PERTH, Australia - Crews searching for the missing Malaysia Airlines jet are racing toward a patch of the southern Indian Ocean to determine whether a few brief sounds picked up by underwater equipment came from the plane's "black boxes," whose battery-powered "pingers" are on the verge of dying out.
A British navy ship is now in the area where a Chinese ship reported detecting a "pulse signal" over the past two days.
The HMS Echo is fitted with sophisticated sound-locating equipment.
Officials say Australian military aircraft are also being sent to the area to investigate. An Australian navy ship with high-tech sound detectors from the U.S. Navy will also head to that area after it investigates a sound it picked up Sunday in another part of the search area.
Meanwhile, a senior Malaysian government official says investigators have determined the missing jetliner skirted Indonesian airspace as it flew from Malaysia to the southern Indian Ocean.
The official says Indonesian authorities have confirmed the plane did not show up on their military radar. He says the plane could have deliberately flown around Indonesian airspace to avoid radar detection, or may have coincidentally traveled out of radar range.