Six things we've learned about missing Malaysia Airlines Flight MH370 as search closes in on black box

The mystery of Malaysia Airlines MH370 could be solved if two black boxes can be retrieved from the bottom of the ocean.           

An Australian vessel picked up the signals from around 14,764 ft below the surface of the southern Indian Ocean, 1,650km off the coast of Perth.

The world is waiting to hear if the flight data recorders hold vital clues in understanding what happened to the plane.

Malaysian acting transport minister Hishammuddin Hussein is hoping for a "positive outcome" from the intense search operation.

For 30 days the plane has been missing and all 239 passengers and crew are thought to have perished.

Here are six things we have learned on a day of extraordinary developments in the hunt for Flight MH370:

What the black boxes contain

There are two black boxes - which are actually universally coloured orange.

They are the flight data recorder and the cockpit voice recorder and the batteries have reached their 30-day life span.

After today they will begin to fade so it really is a race against time to locate them in the remote underwater region.

David Kaminski-Morrow, the air transport editor of the Flightglobal publication, said the flight data recorder reveal if anything went wrong.

But Mr Kaminski-Morrow said the cockpit voice recorder may not be so useful.

He said: "It is likely to only record conversations in the cockpit for the last two hours of the flight and so will not tell us about what might have gone on before that."

MH370's black boxes are thought to be deeper than the Titanic

Signals - or "pings" - believed emitted from the black boxes from MH370 are at a staggering depth of about 14,764 feet That means the elusive devices that record aircraft data are deeper than the wreck of the RMS Titanic.

The vessel sank on its maiden voyage in the north Atlantic on 15th April 1912 and rested at a depth of 12,500 feet.

Retired Australian Air Chief Marshal Angus Houston said the pings "were a most promising lead".

Yet, the black boxes could be so deep the robotic probe Bluefin 21 that will be used to create a map of the area with sonar may not be effective.

The submariner device has a depth capability just less than the reported depth of the black boxes.

Australia signal detection 'more credible' than Chinese

Chinese patrol ship Haixun 01 reported receiving a pulse signal with a frequency of 37.5 kHz, consistent with the signal emitted by flight recorders, on Friday and again on Saturday.

Professor David Stupples believes the "pings" detected by the Australian Ocean Shield are more credible than those picked up by Haixun 01, 340 miles away from the latest signal emissions.

The Ocean Shield has greater sophisticated technology and reported the first detection was held for two hours and 20 minutes before the ship lost contact.

After turning around, the ship picked up the signal for another 13 minutes.

Deputy Foreign Minister Hamzah Zainuddin has confirmed family members of the missing 239 passengers will be brought to Perth.

The Malaysian government minister made the announcement in Kuala Lumpur but could not say when the relatives would arrive in Australia.

"We are not so sure as to when. What we are looking at is the wreckage," he said.

"Once we find it we will decide on a set day to bring the next-of-kin to Perth.

"We will announce it as soon as we can."

The US tighten air travel security after MH370 vanishes

The US have been prompted to screen the passports of travellers leaving the country after the disappearance of MH370.

Two passengers on board the missing plane, including 19-year-old Iranian Pouria Nour Mohammad Mehrdad, were travelling on stolen passports, CBS News reports.

Until recently, US authorities only screened passports of those coming into the country.

Mr Mehrdad was understood to have been on his way to Germany where he was hoping to seek asylum and had no links to terrorism.

Conspiracy theories may be quashed by black box discovery

There have been plenty of conspiracy theories aired since Flight MH370 went missing on March 8.

One such theory is that the plane flew to the tiny tropical island of Diego Garcia, in the Indian Ocean.

The island is home to a US Naval Base and was created between 1968 and 1973 during which time the UK used "forced expulsion" to relocate the native population to the Seychelles.

It has had no indigenous inhabitants since they settled on the orders of the British government in the Chagos Archipelago, as well as Mauritius and the Seychelles.

The theory was given some credence when it was discovered that the island’s landing strip was programmed into the home flight simulator of MH370’s pilot, Captain Zaharie Shah.

However, an FBI investigation found “nothing sinister” about Shah's flight simulator files.   (mirror.co.uk)