Malaysia Airlines Flight 370 is missing. That much we know. Unfortunately, what we don't know includes where in the world it might be, let alone what happened to it. But the US Navy is in the Indian Ocean right now, trying to help find it. This is what they're doing.
Part of what we know includes the information that the plane could have travelled along one of two arcs, mainly based on data collected from a single satellite out in space. This is what that map looks like, once again:
The Northern one brings the plane over land, across China, and potentially as far as Kyrgyzstan. The countries in that arc are looking into that flight path, and that involves mainly going back and manually checking radar records.
That could take a while.
The Southern arc is potentially even more fraught. It sweeps way out over the Indian Ocean, containing some of the most remote areas on Earth. There are few ships, few islands, and even fewer people out there. And I really do mean "few." The arc spans from about 1,000 miles west of the city of Perth, Australia, to a zone many miles away from the Heard and McDonald Islands.
Never heard of Heard Island and McDonald Island? That's because they're cold, barren, windswept, and closer to Antarctica than anything else. Nobody lives there. At all.
The Southern Arc is incredibly remote, and few nations have the capacity to send resources that far from humanity, let alone have them actually do anything.
Searching the Southern Arc might take even longer than the Northern one.
The US Navy, along with various tidbits from the Australian Navy, the Indian Navy, and the Singaporean Navy, is searching this southern zone. And it is so, so much worse than searching for a needle in a haystack. I mean, how big is a haystack, six feet by six feet by six feet? That's only 216 cubic feet you've got to search.
The naval search zone, in contrast, contains thousands and thousands of miles, so to cover all that distance you'd need some ships, some planes, and some helicopters.
Here's how the US Navy does it.
The P-3C Orion and P-8 Poseidon
To cover vast distances relatively quickly, the US Navy needs to use airplanes. Specifically, it uses two varieties normally intended for wartime reconnaissance, the P-3C Orion and the P-8 Poseidon. The P-3C, the older of the two, is based on the old Lockheed L-188 Electra airliner. The US has used the type since the early 1960s, and it's main search tool is readily apparent, looking like a stinger attached to its behind.
That stinger right there is known as a MAD boom, but "MAD boom" isn't just how you refer to the latest major plot point in a Michael Bay movie. MAD, in this case, stands for Magnetic Anomaly Detector. The science behind the MAD is incredibly complex, but I'll try to explain it as simply as possible. Basically, the Earth is one big giant magnet, with all that swirling molten iron inside generating some pretty big forces.
But if you drag a big metal object over its surface, that creates a disturbance in the magnetic field. The MAD senses that disturbance in the magnetic force, and can then tell its operator that there's something below the detector. MAD systems were originally introduced to find Soviet submarines, but they can also be used to find a plane, if it's underwater. Malaysia Airlines Flight 370 was a Boeing 777, which is more than 200 feet long, and Boeing 777s are made mostly out of metal. Naval officials have said that the P-3C can detect objects roughly the size of a basketball, so if there are any remaining bits of the MH370 that are big enough, the MAD should find it.
Unfortunately, the part of the Indian Ocean that's being searched can be over 12,000 feet deep, and unclassified reports are unclear on whether the MAD is able to reach that far down, especially for smaller objects. So that's where the Orion's kid brother comes in.
That younger sibling is the P-8 Poseidon. Intended as a replacement for the P-3C Orion, the Poseidon is based on the Boeing 737, an airliner you've probably flown on before. The P-8A's used by the US Navy weren't fitted with a MAD in an effort to save weight, but instead, it's got something known as an AN/APY-10 radar, which should be able to spot any bits floating on the surface of the water.
Older radars, when pointed down from a plane, would have a hard time picking up something from the background of the ground or the water it was atop of. The AN/APY-10 is supposed to be more advanced, able to pick a small piece of anything out of the water that it floats on top of. If something is floating out there, in the thousands of miles a P-8 will be able to cover in a day, that radar, in addition to a lot of other cameras and sensors the P-8 has, should be able to spot it.
But let's say the Orion and the Poseidon don't find anything, which is entirely possible. Or they do find something, but they can't investigate it. It's not like they're equipped do just open the door and push a frogman out the hatch to check it out. That's where the helicopters come in.
The MH-60R Seahawk
The US Navy fleet contains over 60 Arleigh Burke-class destroyers. At over 500 feet long, and weighing over 9000 tons, they form the backbone of the fleet. One of their most potent weapons, however, isn't some type of gun or torpedo mounted on the side. Instead, the weapons are out the back. They're the two MH-60R Seahawk helicopters.
The USS Pinckney was one of the first ships on scene, helping to comb the ocean. It eventually had to return to Singapore for previously scheduled repairs, so it's now been relieved on station by the USS Kidd, which carries two Seahawks of its own. The Seahawks, with a top speed north of 180 miles per hour and a service ceiling of 13,000 feet, can also fly low and slow if need be. Even still, they've got a range of 245 miles, which is a lot of ground, or, in this case, ocean, to cover.
One of the Seahawk's main missions is Search & Rescue, and in that capacity, one of its main tools in the search is what's known as a FLIR, or "Forward-Looking InfraRed" camera. It's basically a camera hooked up to a TV screen, except instead of taking normal video using visible light, it takes pictures using light on the infrared part of the electromagnetic spectrum. Looking for something on the infrared spectrum means that you can see differences in heat, so if a piece of metal is on the surface of the ocean, baking in the sun all day, there's a good chance it'll stand out nice and bright from the relatively cool water around it on the images from the FLIR camera.
Of course, that's if it and the other radar and sensor systems the MH-60R has spots anything at all. Because the destroyer that carries the MH-60R has an even more powerful sensor suite aboard than anything the helicopter could carry.
The USS Kidd
The USS Kidd, an Arleigh Burke-class destroyer, normally carries a complement of somewhere around 380 officers and enlisted sailors, as opposed to the Seahawk, which carries a lot less than that. And those 380 people are the most powerful sensor there is, as 760 eyes can determine what looks like a piece of plane and what looks like random floating garbage in the water, of which there is plenty in the Indian Ocean, better than a lot of radars can.
And, weirdly enough, human eyes and brains are the decidedly low-tech sensors that are the crux of the Navy's search strategy, even aboard the planes and the helicopters, but especially aboard the destroyer. Seriously, look at the plain paper chart the Kidd's commanding officer uses to lay out the search area:
Extra lookouts have been assigned on the decks of the Kidd, for 24-hour coverage, and even people who don't normally stand watch are doing their part in manning the rails, according to the Navy. In fact, the Kidd's engineers have gone so far as to rig a whole bunch of extra lights off the structure of the ship, just in case someone spots something at night.
Of course, there are other tools as well, that are being used by every vehicle involved in the search. These include sonobuoys and hydrophones, which are basically microphones that are dunked into the water, and can listen for the audible "PING!" sent out from an aircraft's black box, sunk deep in the water.
It's weird, though, to think that with all of the most powerful tools that money can buy, people are still the primary resource.
And we still haven't found anything.
UPDATE #2: Reader Daniel MacCabe chimed in to make a great point about the P-3 Orion and the use of MAD:
former P-3 pilot here. I just want to clear up some misconceptions about our mighty Maritime Patrol Hunter.
MAD is a secondary or tertiary method at best. It requires a metal object to influence the magnetic lines of force created by the earth, so it needs a target that is made of ferrous metal. A Boeing 777 has very little ferrous metal in it's structure and would be a virtually impossible thing to pick up on MAD. The range on MAD is also very limited, if the plane was at the bottom there would be no hope.
The P-3 does have a very good surface search radar and great visibility. Primary search will be with the radar and the crew's eyeballs. They may also drop a passive sonobouy every now and then to listen for the Black Box's pinger.
The Orion will be cruising around at less than 1000 feet and normally with one, or maybe even two engines shut down to increase their time on station. There is absolutely no better way to perform wide area maritime surveillance than the mighty Orion.
Photos credit: US Navy, the Office of the Malaysian Prime Minister, Mark Wagner