In short:
A team has completed a fresh search to find the remains of 20 American servicemen killed when a military plane was shot down off the Western Australian coast in 1942.
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plane → complete → 1942
It is part of ongoing efforts to recover the remains of 80,000 American service personnel missing globally, and locate thousands of wrecks undiscovered in Australian waters.
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It → recover → waters
Volunteer wreck-hunters are planning a fresh search for the warplane next month in waters near Broome.
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hunters → plan → Broome
The US government has launched a fresh mission to find an American aeroplane missing in Australia's northern waters, more than 80 years after it crashed, killing more than a dozen men.
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it → launch → men
It is the latest in a series of expeditions aimed at finding the thousands of shipwrecks and sunken planes that lie unrecorded in Australian waters — many containing human remains.
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that → aim → remains
The latest search was funded by the US Department of Defense, in a bid to recover the remains of soldiers killed when a US Liberator plane was shot down by Japanese fighter planes near Broome in 1942.
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plane → fund → 1942
"It's a bit of needle in a haystack kind of scenario," says maritime archaeologist Jane Mitchell, who led the expedition.
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who → say → expedition
"We didn't find it this time, but we've been able to rule out an area of about 15 square kilometres, so in that sense, no result is still a result.
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result → find → sense
[The crash] is still in living memory and there are families wanting to know what happened to their loved one, so it's an honour to have the opportunity to try to answer some of those questions.
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it → live → questions
"
Thousands of wrecks
More than 11,000 boat and plane wrecks lie in Australian waters, but only about one-quarter of them have been located.
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quarter → lie → them
Some are boats sunk hundreds of years ago, such as Makassan and Dutch vessels.
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Some → sink → vessels
Others are aeroplanes shot down in wartime, navy boats sunk in battle, or luxury liners such as the SS Koombana, which sank, killing 150 people.
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which → shoot → people
It has never been found.
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It → find → ?
With search technology becoming cheaper and more accessible, authorities are expecting a spike in discoveries in the coming years.
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authorities → become → years
We've really seen in the last 10 years how technology has come along, and suddenly it's making these sites much more accessible," says maritime archaeologist Ross Anderson.
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Anderson → see → years
"Along with increased seabed mapping, I think we're going to see a peak and a rise in new discoveries."
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we → increase → discoveries
A global search
The most recent search for the Liberator was commissioned by the US Defense POW/MIA Accounting Agency, which oversees a database of more than 80,000 defence personnel whose bodies have not been recovered.
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bodies → commission → personnel
The agency's historian Dan Kosasa says about 280 of those are believed to have died in Australian territory.
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280 → say → territory
"Recovering the remains of our missing personnel and returning them to their families is our agency's mission, and we go to exceptional lengths to accomplish this mission," he says.
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he → recover → mission
Even after 80 years, the unit is getting tip-offs from Australia.
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unit → get → Australia
"Just recently, the agency learnt of a lead in which some personnel working at a navy yard in Australia during the war may have discovered American remains in the wreckage of a vessel they were repairing and buried them without notifying the US government," Mr Kosasa says.
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Kosasa → learn → government
In search of 'the Holy Grail'
Helping solve the maritime mysteries are amateur enthusiasts such as Jim Miles.
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enthusiasts → solve → Miles
The retired military pilot has been searching for the Broome Liberator wreck for 15 years, towing a side-scan sonar from his catamaran to scour the sea floor.
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pilot → search → floor
The small device emits pulses reaching 50 metres that are fed back to create a digital image of every bump and object.
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that → emit → bump
"It's hard to believe that all around Australia there are still these missing wrecks," he says.
"
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he → believe → Australia
Finding them is a bit of drug, to be honest.
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Finding → find → drug
"And finding this Liberator is, for me, the Holy Grail."
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finding → find → me
The aircraft was shot down on a steamy wet-season morning in March 1942, just seven minutes after take-off.
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aircraft → shoot → off
It was full of injured and sick American servicemen being evacuated from Java to Australia, and while the records of those aboard are not precise, it is believed at least 20 men died.
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men → evacuate → those
Miraculously, a young soldier from Oklahoma survived and swam for 33 hours to reach shore.
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soldier → survive → shore
Two days after the crash, Sergeant Melvin Donoho staggered into the Broome airbase, naked, sunburnt and close to collapse.
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Donoho → stagger → airbase
The circumstances of the crash create a tantalisingly limited search zone stretching about 16 kilometres offshore.
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circumstances → create → zone
When the ABC joins Mr Miles aboard his search boat, he is moored in the turquoise waters off Broome, marking targets on a nautical map.
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he → join → map
I've got a tip from local fishermen about some possible structure underwater, so we'll head out there and check it out," he says.
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he → get → it
"Most days you don't find anything, but you never know — today could be the day."
uncertain
today → find → anything
Pinpointing an underwater grave requires historical detective work, involving flight manifests, black-and-white photos, tidal charts and witness testimony.
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Pinpointing → pinpoint → manifests
In 2014, he and long-time search partner Dion Marinis found the wreck of an American Beaufighter also shot down during the Japanese attack on Broome.
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he → find → Broome
They were able to meet with relatives of the men killed in an emotional memorial ceremony a few months later.
"When you find a wreck and descend down knowing no-one's seen it since 1942 or whenever … it's a really spiritual moment," Mr Miles says.
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Miles → meet → 1942
"It's always on your mind that you're looking for a site where potentially a lot of people died, and there are families waiting to learn of a final resting place."
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lot → look → place
Ross Anderson, curator of maritime heritage at the WA Maritime Museum, says volunteers play a vital role in documenting Australia's underwater sites.
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volunteers → say → sites
…and 19 more, not listed.
The Aporia