China's Search Vessel Picks up Pulse Signal in South Indian Ocean

http://english.cri.cn/6909/2014/04/05/189s820764.htm

by fla • 12 years ago

66 68 12 years ago

english.cri.cn

podperson4• 12 years ago

Interesting how effective the Chinese have been (relative to the US and Australia) in the search thus far.

z92• 12 years ago

China is heavily involvement in this search as most of the passengers [~150 of 230] were Chinese.

neurotech1• 12 years ago

These same tow sensors and underwater autonomous vehicles are used for submarine hunting. Guess which country has a large number of nuclear submarines? US does. Its expected China would try search for our subs.

peeters3• 12 years ago

I'm not sure you can generalize that. It was a Chinese agency that "mistakenly" posted those misleading satellite images, while the U.S. was the first to draw a connection between satellite data and the Indian Ocean as a possible crash area.

There have been mistakes, false leads, and promising revelations across the board.

k-mcgrady• 12 years ago

> "while the U.S. was the first to draw a connection between satellite data and the Indian Ocean as a possible crash area."

Was it not a UK firm that worked that out?

cflee• 12 years ago

The Chinese also spotted debris on satellite imagery (on an area that had been thoroughly searched) as well as a "sea floor event" (a week after the claimed event) in the South China Sea. I wouldn't jump to the conclusion that this newest finding is an instance of effectiveness just yet.

edit: whoops, 'peeters posted just as I did

podperson4• 12 years ago

Odd to get downvoted for suggesting this is interesting.

1) If China feels it necessary to fabricate sightings in order to mollify its population (also note the way it has tried to manage the bereaved families and focus their anger on Malaysia including providing coordinated t-shirts etc.) then that's interesting.

2) If China, not usually noted as outstanding in air, naval, or orbital surveillance capability is able to outperform Australia (which is both very experienced with ocean searches and is operating on its doorstep) and the US then that's interesting.

3) If China is more willing to reveal its capabilities than the US or Australia that's also interesting. (E.g. I suspect the reason the Australians were so willing to commit to the current search area based on one satellite image is because they actually tracked the flight via Jindalee, but were unwilling to reveal that system's capabilities given there weren't going to be any survivors.)

arrrg• 12 years ago

I assume this search is coordinated and everyone knows the area one ship can cover. That way the same area isn’t examined twice. Wouldn’t it then be simply up to luck as to who finds something?

You can always argue about who sent the most ships and who covered the most ground, but some nation’s ships finding this is not direct evidence for this. I would assume it would be better to determine this directly, not indirectly.

kijeda• 12 years ago

Is the Chinese search part of the Australia-led search effort (i.e. the Chinese vessels are searching areas they are being tasked), or are they doing their own independent search?

pavelrub• 12 years ago

How effective have they been? So far China has found absolutely nothing.

If anything, they have been overly enthusiastic to quickly report partial results based on incomplete or bad analysis, which then turned out to be nothing at all.

podperson4• 12 years ago

I agree. I should probably have put quotation marks around "effective".

InclinedPlane3• 12 years ago

That's just post hoc fallacy. There are a lot of vessels searching from a lot of different countries. Whoever gets lucky is going to seem more effective, but luck is probably a majority factor in this case, given the size of the search area.

podperson4• 12 years ago

It's hard to analyze data before it's available!

Aside from this announcement, Chinese have also (apparently) seen more stuff from planes and satellites than anyone else, despite -- for example -- lacking the P3 Orion and the P8 Poseidon, and not having much blue water navy experience, and it not being just off their coast.

We had big fanfare over the number of P3s the US and Australia were committing to the search, and the addition of the P8, and the deployment of a special US Naval vessel with dedicated sensor array. Since then the only nation to report positive sightings (more than once) has been China. Interesting no?

daturkel3• 12 years ago

Incredible last minute discovery considering that they're only relying on it to continue pulsing until tomorrow.

kapkapkap• 12 years ago

30 days is not by any means a firm deadline for the blackboxes. They are designed to last a minimum of 30 days and usually do last a lot longer.

headShrinker• 12 years ago

The signal, at 37.5 kHz per second, was picked up by a black box locator at 25 degrees south latitude and 101 degrees east longitude.

Hz per second? Hertz is a per second unit of measure...

Nogwater• 12 years ago

Maybe it's an accelerating frequency, like a chirp? :)

ericbarch• 12 years ago

I think they're referring to the fact that it sends the pulse once per second. Could have been worded differently.

PakG1• 12 years ago

"each second" perhaps.

wglb2• 12 years ago

Yep, but they did get it right a little further down the article.

But what is the monitor an acoustic wave--isn't it a radio signal?

mikeash• 12 years ago

Radio doesn't penetrate water well. It also emits sonar pings for the case where it's in water.

dannypgh• 12 years ago

No, it's an acoustic wave. Salt water is a good conductor of electricity, as such only ultra low frequency radio has any chance of penetrating more than a few feet, and the antenna needed to pull that off is prohibitively large for an aircraft.

mschuster912• 12 years ago

I think it's time for the FAA/JAA to make a regulation that blackbox batteries have to last 3 months or longer. Should not be too much of a cost to retrofit, compared to stuff like live FDR transmission via satellite.

twic• 12 years ago

I wonder if they could fit them with auxiliary saltwater batteries. So they have N days of power from the main battery, then an additional M days if they land in the sea. Given that it takes a lot longer to find crash sites at sea, that's the main place they need extra energy.

That said, i have absolutely no idea if a saltwater battery actually has a higher energy density than some other kind of battery. Probably not.

jonsen• 12 years ago

If it separated from the plane and floated, it could be sunlight powered.

peeters3• 12 years ago

It's hard to design for outlier data. This is the most unusual search in modern aviation history. It is the outlier. With a couple of exceptions, all crash zones are found within days.

What makes you think that increasing the battery by a couple of months will deal with the next extraordinary case? What you're suggesting isn't even an order of magnitude more, though 30 days is already a couple of orders of magnitude more than what is needed 98% of the time.

Hindsight is 20/20.

kenrikm• 12 years ago

Or just automatically eject floating GPS beacons on impact. You only need one good ping to the satellite to define the crash area.

This is not the first time this has happened. After Air France there should have been some added location method, it took two years to find the black box.

hughlomas• 12 years ago

Similarly, I've heard that the cockpit voice recording only keeps the last two hours. While that deals with 99% of the cases, here it will miss out on all conversation near the point that the flight began to go off course, and indeed hours after that.

What would be the cost to simply bump the recording time up closer to the maximum flight time possible on a full tank?

tzs3• 12 years ago

You wouldn't necessarily need to increase the battery capacity. You could increase the time between pings. First week after activation, ping at the rate they do now. Then start increasing the interval.

The idea would be to have some pings still happening even after a very long time, because if it gets to that point it is clear no one knows where to look and the thing is only going to be found by accident, when something that listens for other reasons (submarine, research vessel) happens to pass near it.

FatalLogic• 12 years ago

There already are such regulations on the way. The European Aviation Safety Agency and the FAA are both likely to start airlines switching over to 90 day batteries within a year or two. The EASA is also looking at increasing the range of the locator ping (by adding an additional lower frequency pinger for planes that do long trans-oceanic flights, I think), and extending the voice recording time from 2 hours to 15 hours - perhaps the FAA is planning something similar.

http://www.flightglobal.com/news/articles/mh370-loss-coincid...

http://www.newscientist.com/article/mg22229634.500-five-ways...

opencheckbook• 12 years ago

Ok great idea philosopher king, let's make the regulation to demand 90 days ping endurance.

Just one caveat, make sure you open your checkbook for this one, not the rest of us who don't want to pay for yet another trivial feature creep crap every time we buy a flight ticket.

mschuster912• 12 years ago

Better pay for the fact that in case my plane crashes into the ocean, the plane will be found instead of paying for useless magazines/newspapers I don't read anyway...

dang• 12 years ago

Please don't make aggressively sarcastic comments on Hacker News. It goes against our two most important values: signal/noise ratio and personal civility.

InclinedPlane3• 12 years ago

You're just patching a specific bug by adding a special case for it. That's no way to engineer anything. Also, you use the typical fallacy of a fix being just a minor bit of work. If it was low cost and easy to do it'd be done already. Batteries are big and heavy. Increasing the size and weight of the black box is a tricky proposition because it would make it more vulnerable to damage, so you'd need to re-engineer the whole thing to make it stronger. That would make it much heavier and much larger than it's been. And because of such major engineering changes you have to completely redo every aspect of testing. Then you have to begin manufacturing new ones and replacing them in every single plane out there. And every single plane now needs to be extensively retrofitted and updated.

yogevyuval• 12 years ago

Is this 37.5 kHz is a standard frequency for black boxes?

MrMeker• 12 years ago

Yes

daturkel3• 12 years ago

"The pulse signal with a frequency of 37.5 kHz is the standard beacon frequency for both so-called black boxes -- the cockpit voice recorder and the flight data recorder, CNN quotes Anish Patel, president of pinger manufacturer Dukane Seacom, as saying. "They're identical.""

ttflee3• 12 years ago

Could it be possible that another black box happened to be found there?

EDIT: I'm just asking a question. Why the down vote anyway?

sschueller• 12 years ago

yes, http://en.wikipedia.org/wiki/Underwater_locator_beacon

analog31• 12 years ago

Dukane Seacom... is that the same company that made the filmstrip projectors that we dreaded so much in elementary school? Maybe that's where they got the idea for the beep from.

Sure enough, same company!

myth_drannon• 12 years ago

to see it on the map try http://itouchmap.com/latlong.html with lat: -25 long: +101

Sorry I couldn't find a map service that I can share the point

bdz• 12 years ago

https://www.google.com/maps/place/25°00'00.0"S+101°00'00.0"E...

davidw• 12 years ago

Interesting - there's a bunch of detailed satellite imagery in the general area they've been searching:

https://www.google.com/maps?q=25%C2%B000%2700.0%22S+101%C2%B...

I'm guessing that this is because of the crash.

wglb2• 12 years ago

Hard to get much further from land.

supernova87a• 12 years ago

I would suggest to the regulatory/FDR/CVR manufacturers a change to the black box spec, which causes the pinger to only begin pinging 7 days (or some threshold) after the crash.

The first few days of pinging are generally useless anyway, because I have not seen any search where a sea vessel was remotely prepared to search in the right area or with the right equipment.

Incorporate this delay period (in the absence of anything else), and at least you get an extra week out of the search potential time window.

dredmorbius2• 12 years ago

Your assumption is false. There have been a few notable cases of flight-over-water crashes in which the correct zone wasn't found quickly, but in the case of flight 137, ships were over the presumed crash zone within hours of the aircraft turning up missing.

In other cases, particularly where the crash itself was visually observed (US Airways 1549, Ethiopian 961, and others) where a multi-day delay in starting pingers would have been counterproductive.

It's also useful to realize that any change you make on flight recorders applies to all equipment, needs to be replace on existing aircraft, and concerns a system which has to work with very high reliability.

tzs3• 12 years ago

In some cases a delay in starting the pinger would delay finding the recorders, but does that actually cause any noticeable harm?

It is important to find the crash site quickly, in order to help any possible survivors, but the pingers do not help with that, do they? Aren't survivors found visually or by the emergency locator transmitter?

It could delay the forensics investigation, but that usually takes years to reach a conclusion anyway and depends on inputs other than the recorders, so it is not clear that getting the recorders is even on the critical path for that investigation.

On a different note, I wonder if it would make some sense to have echoers instead of pingers? That is, instead of automatically sending out a periodic pulse, they would listen for a pulse and then respond.

zmanian• 12 years ago

Ever since it became clear that MH370 fell through a gap in the civilian air traffic control system. This has been a story where various nation states cautiously disclose surveillance capability in order to satiate public demand for information.

lutusp• 12 years ago

Quote: "The signal, at 37.5 kHz per second ..."

I haven't seen this construction since the early 1960s, when the new SI units came into use and people were still confused about the meaning of "Hertz". "KHz per second" literally means "thousand cycles per second, per second".

China's Search Vessel Picks up Pulse Signal in South Indian Ocean

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