Many theories still persist about the missing Malaysia Airlines Flight 370, and no definitive clues have surfaced. The clock to save any potential survivors began ticking the moment the flight sent its last radar signal March 8. But another countdown is also on the horizon.

If the MH370 black box isn’t found in the next 12 days, it may not be found for several years — if ever.

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The BBC created a graphic showing where the black box was mounted on the Malaysia Boeing 777-200. (Image via BBC News)

Flight data recorders, widely known as the “black boxes,” do have a specific lifespan. And in the Boeing 777-200, the minimum expected battery life for this black box model is 30 days.

“It’s required to last a minimum of 30 days,” a spokesman for Honeywell, a manufacturer of airline black boxes, told TheBlaze. “But often they can last longer.”

That doesn’t mean the data saved within the device will be lost after the battery runs out, but it does mean the pinging, or the active sonar, will stop. This will make it incredibly difficult to find the wreckage, even with a sophisticated listening devices the U.S. Navy has deployed to the region, called the towed pinger locator, or TPL.

“The towed pinger locator is a passive system [that listens] to hear the pinging of a black box,” Navy Lt. Cmdr. William Marks, a spokesman for the 7th Fleet, told TheBlaze. “But we have to have a general search area identified before the locator goes in the water.”

Marks said black box pingers are generally not that powerful, emitting sound for only a few thousand meters. The TPL-25′s “listening” radius is just 2 miles — one mile in either direction, and the passive hydrophone system is towed at approximately 3 knots about 1,000 feet off the sea floor.

Naval Systems Sea Command spokesman Chris Johnson told TheBlaze that the Navy has used different variations of the TPL for roughly 20 years to find military aircraft wreckage and black boxes — which are actually painted either orange or yellow in color so it is easier for recovery crews to spot.

The Towed Pinger Locator-25

The Towed Pinger Locator-25 “listens” for sounds within a certain range and though it can operate at depths of up to 20,000 feet, it has a search radius of just two miles (Image source: U.S. Navy)

“This variant in particular has been in use since 2010 and we first used it to locate a downed Harrier in the Gulf of Oman,” Johnson said. “We used a predecessor of this [system] to look for the Air France wreckage, but we did not find the pinger in that case … because that transponder was not working.”

It took search teams two years to locate and recover the flight recorders from the Air France Flight 477 crash into Atlantic in 2009.

An aviation expert who spoke to TheBlaze but asked not to be identified because his employer is closely tied to the flight investigation said the chain of custody for the black box may not even be established yet if it is found in the next few days.

“If the plane is found in international waters by the military search teams, likely the recorder will be turned over immediately to the Malaysian government, but who knows if that has even been discussed yet — this investigation has been confusing and some would say mishandled from day one,” he said.

Best case scenario: the Malaysia Flight 370 recorder will continue to ping for several additional weeks, and new information will continue to narrow the investigation site, such as a French satellite possibly finding 122 pieces of new debris. The cockpit voice recorder will maintain the last two hours of audio in the cockpit, and the flight data recorder records the last 25 hours of flight information.

The faster the Navy can get the TPL in the water, the better odds that the black box will be found. But the locator won’t even go in the water until the Australian government gives the go-ahead, similar to the air-tasking orders it is coordinating now for the aerial search effort.

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The BlueFin 21 is an active sonar that will be deployed once the search crews have determined there is a searchable area (Image source: U.S. Navy).

If the Navy does get a vector and search area with good leads on the wreckage, they also have an active sonar system, called the Bluefin-21, that has side-sweep capability which can get a picture of the ocean floor.

“[It would identify] for example if there is a piece of the fuselage or a tail section,” Cmdr. Marks said. “But really you don’t want to send either of these out there if you are just guessing at an area that is hundreds of miles wide.”

So for now, the search continues by air and by satellite.

If the flight data recorder is found along with the rest of the plane, it will be brought up to room temperature, dried out and then the flash memory is downloaded “so the information can then be extrapolated for the investigation,” the Honeywell spokesman said.

Boeing spokesman Doug Alder told TheBlaze that the company would not reveal which manufacturer built the specific black box on Malaysia Flight 370, but that Boeing does have representatives assisting in the search as technical advisors to the National Transportation Safety Board and will assist in the recovery of flight data when the flight recorder is found.

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