The search for Malaysia Flight 370 has officially been put on pause and the lead government agency says the area the teams have focused on is likely the wrong spot to find the missing plane.
The Joint Agency Coordination Center, Australia's coordinating agency for the multinational search efforts, announced Thursday that the primary target area has been ruled out.
"The Australian Transport Safety Bureau (ATSB) has advised that the search in the vicinity of the acoustic detections can now be considered complete and in its professional judgement, the area can now be discounted as the final resting place of MH370," the agency said.
This announcement, coupled with claims Thursday that the pings heard in the search area may not have been from the aircraft locator beacon but rather from stray noises from the search ship or from one of the listening devices itself, brought weeks' worth of search efforts into question.
"Our best theory at this point is that (the pings were) likely some sound produced by the ship ... or within the electronics of the Towed Pinger Locator ... always your fear any time you put electronic equipment in the water is that if any water gets in and grounds or shorts something out, that you could start producing sound," Michael Dean, the U.S. Navy's deputy director of ocean engineering, told CNN.
But Christopher Johnson, Naval Sea Systems Command spokesman, told TheBlaze those comments needed further clarification.
"While not inaccurate, those comments were definitely premature, and it's really for the Australian government to comment on, not the Navy," he said. "The underwater search portion is over based on the data collected the JACC."
Bill Gibson, general manager of Phoenix International, the company that located and retrieved the Air France locator beacon and black box, said he is still hopeful that the pings will give important leads for the search, especially as the effort is opened up to private industry.
"Sounds travel very differently underwater, and noises like a ping from the locator can get trapped and travel through thermoclines, so you can hear sounds in one location that could have traveled from two or three miles away," Gibson told TheBlaze.
Phoenix International is under contract with the United States Navy to provide deep-sea search operations. Their Artemis Autonomous Underwater Vehicle, dubbed the Bluefin-21, and the Towed Pinger Locator, or TPL-25, were used for weeks as the primary listening devices on the hunt for the black box.
Technicians work on the Artemis autonomous underwater vehicle prior to the ADV Ocean Shield slipping from the wharf at HMAS Stirling on May 10, 2014 in Rockingham, Australia. (Getty Images/Paul Kane)
"It isn't unusual, and we have seen it before, that after being damaged the pinger could transmit at a different frequency band, and we've seen that before," Gibson said. He noted the general public assumes the data recorders and the tracking devices will remain "pristine and perfect" but emphasized in airplane crashes the debris, even the famed black boxes, can be torn apart.
"In the case of Air France 447, the pinger wasn't even attached to the flight data recorder, probably as a result of the impact of the crash," he said.
Gibson said many speculators have compared the Air France and Malaysia Flight events, but he says the two situations are very different, primarily because the search teams did have the last known location of the Air France flight to work from, and they located an initial debris field.
Though their accuracy was brought into question Thursday, it appears the listening devices used by companies like Phoenix are still the best bet for finding the aircraft wreckage, if it did crash into the southern Indian Ocean.
"The towed pinger is a listening device, and it will pick up and receive noise and sounds in the water," Gibson said. "It is designed to listen for a 37.5 kHz signal which is the signal, the frequency, for a pinger like one found in the black box or flight data recorder. But it is designed to pick up all that noise -- the noise from the ship, noise from the marine life -- there is an abundance of noise in the environment and you will be able to see those frequency signals as the TPL is listening and then recording those sounds."
Gibson emphasized that the operators of the listening devices have decades of experience and are trained to know the difference in the sound frequencies. He also noted there is no marine life or environmental occurrence that will generate the 37.5 kHz frequency, which is why this is designated as a specific frequency to be used in locator beacons.
"It's not unusual, that you will pick up on the noise from a ship moving through the water. Any noise on the ship, the engines for example, will be picked up and that sound has a frequency," he said. "Our operators are trained to identify and key on the frequency band of 37.5 kHh."
Gibson said the next step in the search will include "invitations to tender" — an international term for contract requests — from the Australian government asking industry specialists to conduct the next phase of the search.
Australia's lead search vessel, the Ocean Shield, is scheduled to return to port around May 31. Gibson said he expects the invitation to industry to be published then.
Johnson noted the U.S. Navy is finished with its part of the search, but would be prepared to assist again if asked.
"This was an excellent opportunity to work with our international partners on an important mission, and at the end of the day we would help again if asked by the local governments," he said.
Here's another close-up look at the Artemis AUV that has been searching for the wreckage:
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