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Relatives of passengers on Malaysia Airlines Flight MH370 pray at Lido Hotel in Beijing after a Chinese military aircraft spotted several "suspicious" floating objects in remote seas off Australia, increasing the likelihood that the wreckage of the plane may soon be foundReuters

Following a cluster of debris being sighted, the US Navy has dispatched is high tech black box locators to an area of the southern Indian Ocean which is being searched for the missing Malaysia Airlines MH370.

"If debris is found we will be able to respond as quickly as possible since the battery life of the black box's pinger is limited," Commander Chris Budde, US Seventh Fleet Operations Officer, said in an emailed statement.

How Does a Plane's Black Box Work?

Commercial airplanes and jets are equipped with a cockpit voice recorder and a flight data recorder, two separate pieces of equipment which are jointly referred to as a 'Black Box'. In the event of a plane crash at sea, each recorder has a piece of equipment fitted to it called an Underwater Locator Beacon (ULB). The device is activated upon contact with water and can transmit from a depths as low as 14,000 feet (4267m).

What is a Black Box Tracker?

The tracker is reffered to as a "Towed Pinger Locator 25". It is a hyper-sensitive hydrophone that can locate black boxes on commercial aircraft to depths as low as 6000 metres (19685ft). The technology can play a pivotal role in the search for the Boeing 777's black box before its signal dies.

"The system consists of the tow fish, tow cable, winch, hydraulic power unit, generator, and topside control console", according to the US Navy Fact File. "The tow fish carries a passive listening device for detecting pingers that automatically transmit an acoustic pulse. Commercial aircraft pingers are mounted directly on the flight recorder, the recovery of which is critical to an accident investigation."

The Process

"The Pinger Locator is towed behind a ship at slow speeds, generally from 1 - 5 knots depending on the depth. The received acoustic signal of the pinger is transmitted up the cable and is presented audibly, and can be output to either a Oscilloscope, or Signal Processing Computer. The operator monitors the greatest signal strength and records the navigation coordinates. This procedure is repeated on multiple track lines until the final position is triangulated."

A Race Against Time

The search operation is a race against time since the signal of the black box is expected to last only for 30 days. The Malaysia Airlines MH370 went down on March 8, meaning that it has been over 15 days since the time of crash.

Sighting Offers Optimism

On Sunday, the sighting of a wooden pallet and other debris that could be linked to the Malaysian MH370 jet served as an indication that the hunt was finally on the right track. The development comes following over two weeks of false leads and dead ends in the search for the missing passenger jet.

Australian officials said the pallet, along with belts, was spotted on the weekend in a remote stretch of the Indian Ocean. Since then, it that has become the focus of the search. The location of the area happens to be around 2,500 kilometres southwest of Perth.