Search Ships Head Toward Location of Possible Malaysia Airlines Signal

Search ships with sophisticated sound detectors were heading for the southern Indian Ocean on Sunday after a Chinese ship said it detected two acoustic signals deep underwater. The pings may have been emitted by the missing Malaysia Airlines Flight 370's black box, which, if found, will give clues as to what happened to the jet. The signal is designed to fade after 30 days, but time is running out: the plane went down on March 8.

The ships heading for the signal are the British navy's HMS Echo and the Australian Navy's Ocean Shield. Both ships have onboard technology designed to detect deep underwater signals sent by in-flight recording equipment. The Echo was sent right away, but Ocean Shield is reportedly investigating another possible signal before making its way toward the location reported by the Chinese ship on Saturday. The Echo, at least, is expected to arrive at the site early Monday.

Still, officials are urging caution. Although the signals are "an important and encouraging lead," said Australian Air Chief Marshal Angus Houston on Sunday, the reports are as yet unverified. "We have an acoustic event," he explained. "The job now is to determine the significance of that event. It does not confirm or deny the presence of the aircraft locator on the bottom of the ocean." He did note that the characteristics of the reported signals are "consistent with the aircraft black box."

Meanwhile, a U.S. pilots' association has called for an effort to replace the high-frequency radio links used by many planes with satellite technology. A mandatory move to satellites, which are less vulnerable to interference than radio, would make it easier for officials to track flights out of air traffic controllers' reach. "Technology that exists today can pinpoint the location of aircraft in near real time and, in this day and age, it is unacceptable that the location of the aircraft is unknown," the Air Line Pilots Association said in a statement.