Quoting sipadan (Reply 247): it was pretty clear (like beyond obvious) that my words were written in jest and with a facetious tone

As with other forum members, I read your words with my eyes, which do not obviously *hear* a facetious tone.

Quoting sipadan (Reply 247): This was more than apparent from the content of my other posts,

Uhm, not to me and a lot of other readers who don't necessarily want to figure out what you *meant* in previous posts where you have been equally hostile and generated pushback from other posters about your vituperative nature.

Quoting sipadan (Reply 247): So, again, to make this assertion belies even the lowliest denominator of common sense...I can't believe you are going to stand by this assertion...for the sake of what??

I fail to understand your purpose in any of your posts other than to argue for the sake of argument. It is one thing to assert that someone is wrong, it is an entirely different matter to insult someone as a counterargument for your own point of view. As Kalahari notes, there are a lot of highly experienced professionals in these forums (who can honestly disagree with one another), but the only poster here who succeeds in looking "disingenuous, manipulative, and deceitful," not to mention rude, obnoxious, and foolish is you.

Quoting vvbkumar (Reply 250): Pardon me if this has been covered already, it sounds strange to me that if the black box is indeed located before any wreckage is actually confirmed / identified; Unless of course the plane was ditched and it drowned.

Well its been covered a gazzilion times, we are at thread 50!!!.

I could be the case that the back part of the plane sank and has the CVR and DFR and of course the pingers, and the small amount of wreckage has been moved by currents and wind elsewhere.

The ditching (in one piece) in my humble is an almost imposible occurrence due to the size of the engines, the drag created by them would break the fuselage or do a big cartwheel.... so Id guess at least some small parts like seats or pillows would float as debris, after 3 weeks on that sea, its a big difficulty spotting them or finding them if they are not really big...

If they found the black (orange) boxes, I will eat my hat too.... (with a lot of tabasco sauce)

TRB

Quoting WarrenPlatts (Reply 244): the Inmarsat folks actually were using the same ping rings given at duncansteel.com--they can be trusted IMHO.

I think you've got that backwards. Inmarsat has the data. duncansteel.com does not have the data and he has merely reverse-engineered what the rings might have been based on a number of assumptions.

Quoting Kaiarahi (Reply 248): I suggest you take your time (it takes more than 3 weeks) to learn who the respected contributors are and refrain from insulting them, for all of our benefit.

   perhaps he can settle down and start making a contribution in the future.

Quoting vvbkumar (Reply 250): Pardon me if this has been covered already, it sounds strange to me that if the black box is indeed located before any wreckage is actually confirmed / identified

There is apparently a large and scattered debris field 56 miles from where the ping was heard. They are working to pick up/identify those objects now (it *is* night time in that part of the world right now - all this seems to have happened pretty much right before dark).

Again, it is possible that *all* this turns out to be nothing. It is also possible that it turns out that the ping is from the recorders and the debris field is from the plane. We just need to be patient and find out which it is, which definitely won't happen until at least tomorrow in Australia. But there's nothing "strange" about it as things stand now.

Quoting Theredbaron (Reply 252): If they found the black (orange) boxes, I will eat my hat too.... (with a lot of tabasco sauce)

Hey we'll all gladly join in on the feast. Boy I really do hope they have found it.

Quoting Theredbaron (Reply 252): If they found the black (orange) boxes, I will eat my hat too.... (with a lot of tabasco sauce)

I wonder how long China's been listening for them. Not a lot of media coverage of that... much more about a US Navy asset getting to the scene.

Quoting spacecadet (Reply 254): We just need to be patient and find out which it is, which definitely won't happen until at least tomorrow in Australia.

Sunrise in the search zone is about 0000UTC (2000EDT).

Quoting SSTeve (Reply 256): I wonder how long China's been listening for them. Not a lot of media coverage of that... much more about a US Navy asset getting to the scene.

It appears they are on their own and not reporting to joint task force in Perth. They do have a manned submersible capable of going 7000+ meter depth a unique capability no one else has.

http://en.wikipedia.org/wiki/Jiaolong_%28submersible%29

Quoting DTW2HYD (Reply 258): It appears they are on their own and not reporting to joint task force in Perth. They do have a manned submersible capable of going 7000+ meter depth a unique capability no one else has. http://en.wikipedia.org/wiki/Jiaolong_%28submersible%29

They also could keep this ship on standby and not assigned to a specific search area because of it's capabilities, in case another ship finds something, they can move there quickly to check out the findings.

Jan

Quoting Kaiarahi (Reply 257): Sunrise in the search zone is about 0000UTC (2000EDT).

Sunrise in Perth is about 0631L, they're +8 so that's 2231Z. If by EDT you mean Eastern Daylight Time like in Toronto or New York City, that's another -0400 so 1831EDT or 6:31PM or... in about 3 hours from this post.

We in Eastern time are pretty lucky that all we need to do is add a day and flip AM/PM and we've got the local time in Perth.

[Edited 2014-04-05 12:26:55]

Quoting nupogodi (Reply 260): Sunrise in Perth is about 0631L, they're +8 so that's 2231Z. If by EDT you mean Eastern Daylight Time like in Toronto or New York City, that's another -0400 so 1831EDT or 6:31PM

Simpler just to use GMT, isn't it? People around the world know how many hours ahead/behind they are where they live.

[Edited 2014-04-05 13:19:09]

Quoting nupogodi (Reply 260): Sunrise in Perth is about 0631L

Notice I said the search zone, which is west of Perth. Sunrise is approximately 1.5 hours later than Perth.

Quoting art (Reply 261): Simpler just to use GMT, isn't it?

Z = UTC = GMT.

Sorry, had not come across Z. Nor L as a time zone.

[Edited 2014-04-05 13:28:03]

[Edited 2014-04-05 13:31:02]

Quoting WingedMigrator (Reply 253): Quoting WarrenPlatts (Reply 244):the Inmarsat folks actually were using the same ping rings given at duncansteel.com--they can be trusted IMHO. I think you've got that backwards. Inmarsat has the data. duncansteel.com does not have the data and he has merely reverse-engineered what the rings might have been based on a number of assumptions.

You can verify they're in the right ballpark. E.g., on my Google Earth, the distance from the last two ping arcs on the 450 knot path should be 682.5--I measured 690 nm, a difference of 7.5 nm--or 1 minute of flight time. The next distance should be 450 nm, I measured 467--a difference of 2 minutes. Also, remember that google earth assumes a spherical Earth, where as STK which Duncan is using uses a more realistic ellipsoid mode. Given that the accuracy of the ping arc radii are only on the order of plus or minus 50 to 100 nm, that's not bad.

Quoting art (Reply 264):

No worries. Z (zulu) is the abbreviation used in aviation to denote UTC.

And L just means local time, interpretation derived from context.

[Edited 2014-04-05 13:56:53]

Quoting nupogodi (Reply 239): QARs are not crash-proof, so good luck

When they located the AF447 crash site they recovered the ISIS, FCDC, eQAR and FMGEC computers. They were able to extract some memory from the ISIS and FMGEC 1 and 2. The solid-state physics lab at Paris-Sud University attempted to read the eQAR data but very little additional information was recovered.

They specifically target recovery of the engines and onboard computers from the avionics bay in these situations.

This is what they looked like coming out of the water:

Quoting Kaiarahi (Reply 248): I suggest you take your time (it takes more than 3 weeks) to learn who the respected contributors are and refrain from insulting them, for all of our benefit.

Unbelievable we still have to remind people to be civil here.

[Edited 2014-04-05 14:31:39]

[Edited 2014-04-05 14:32:08]

Quoting canoecarrier (Reply 268): Unbelievable we still have to remind people to be civil here.

More so because it's the civil aviation forum

[Edited 2014-04-05 15:10:21]

Quoting DTW2HYD (Reply 258): It appears they are on their own and not reporting to joint task force in Perth. They do have a manned submersible capable of going 7000+ meter depth a unique capability no one else has.

Wow thanks for the info! I really hope they found the black boxes.... (getting ready my hat and some veggies with tabasco sauce)...

(note: on the picture look how they resubmerged the recovered computers to avoid oxidation ...) Good one!

TRB

Quoting WingedMigrator (Reply 242): Point of order: we only have the last ping ring from Inmarsat. The other colors are quite pretty, but calculated based on unknown assumptions.

These graphs are pretty but worthless : They try to fit the last 18:11 ping with a set of fixed speed trajectories which also originate from a point said to be latest known position.

The reasoning is in error in two very important areas :

1/- choosing a fixed origin defeats the ping-derived loci ( Note that there is no attempt from the author to determine a route, or a series of routes that could fit all loci. To find one would be a miracle.

2/- Choosing a set of fixed speeds, if good for an explanation of the analysis invoved, is in fact patently wrong because
2.1 - the effect of wind on drift ( change of direction of the trajectory ) and speed ( the Doppler shifts are based on ground speed,and no other is ignored, or left aside.
Taking the winds aloft values for the day, provided by Tim Vasquez, the latest estimated point would have had a 230° /110 kt wind, which entails a drift of 12° left and a ground speed of 390 klt for a heading of 180°TRUE.
So these constant speeds trajectories are a fallacy.
They're good for an initial simplified understanding of the basic principles of a demonstration, but nothing else and nothing more.
2.2 - The endurance of the aircraft at these different speeds is ignored, meaning that according to the author, it went down, even if it had more fuel left.

REASONABILITY CHECK :
A modern airliner can navigate only on three basic principles on an oceanic flight :
(A) - A waypoint-to-waypoint trajectory : it's an orthodrome or arc of a great circle. It necessitates a working FMGS to ride over the IRU data with the help or not of a GPS... the airplane would still be subjected to the wind effect with varying ground speeds

(B) - A constant TRUE heading reference, which is quite unlikely as we only use TRUE reference at high latitudes -generally around 80° of latitude, North or South : We should see the effect of the winds aloft with varying ground speeds and varying courses due to the varying drifts.

(C) - A constant MAG (netic) heading : here we'll see the aircraft is subjected to the wind - drift and ground speed - and the rapidly changing magnetic declinations..
To illustrate this point, imagine a MAG heading of 180° with a declination of 15°W at the estimated 20:11 locus : This means that the aircraft is in fact flying a TRUE heading of 165°, at which, subjected to a 230° / 110 kt wind, its course would be 150° and its ground speed 415 kt... That's 30° away from a TRUE 180° heading and a 35 kt slower speed.

(D) - Please note : There is no such thing as an *inertial track*

Quoting DTW2HYD (Reply 258): It appears they are on their own and not reporting to joint task force in Perth.

Can you indicate the source for this? While the Australian Joint Agency Coordination Centre has not specifically named the ships or nationalities involved in the search since it moved NW of Perth, the last update from the Australian Marime Safety Authority on 31 March was very clear that seven Chinese ships were participating as part of the Australian-coordinated search.

The JACC statement overnight Saturday/Sunday says Australian authorities cannot verify any connection to MH370, which I interpret as being properly cautious. I think the fact that the statement says the Rescue Coordination Centre in Australia has spoken to the RCC in China to ask for any further information is likely to be a result of agreed communication protocols which reflect language and other communication difficulties.

Quoting cbrboy (Reply 272): Can you indicate the source for this?

Heard it on CNN. They were debating why Chinese ship was in that area and why it was not reported thru Australia and/or Malaysia.

how convenient that a Chinese ship in a random spot managed to hear One (not both devices) ping for a brief period that unfortunately they didn't get to record, but had plenty of pictures of the hydrophone and stalwart rescue crew ready to share with the Chinese domestic press. They even heard it twice (second time just for a minute, also not recorded) so it must be true!
They can't lose with an announcement like this: if nobody else reproduces it, it was just their superior skills. if it gets found somewhere else, well it was the water layers bouncing the signal, or a foreign ship making a clatter. If it never gets found thank goodness the Chinese were around to at least hear the last evidence that the plane is indeed there, somewhere.
very cynical but I can see the temptation to impress with little white lie is too large.
Everyone needs any different county to chime in with a confirm before it can be taken as a real sign.

Well the announcement weeks ago by the Australian PM that wreckage had been found really didn't help in that regard !

Quoting jelliesR (Reply 274):

How do we know the footage of the boat crew w/hydrophone isn't stock footage? Selected to provide cover for their true capability?

FWIW: I don't think the Chinese have anything to gain by creating a phantom contact.

Little more information on pinger locator Chinese used.

It is a Diver Pinger Locator (DPL-275XS) by Teledyne. Same as DPL-275 with extension pole and other accesories to operate from a vessel.

http://www.benthos.com/index.php/product/locators/dpl-275-locator
http://www.benthos.com/index.php/product/locators/dpl-275xs-locator

Quoting jelliesR (Reply 274): how convenient that a Chinese ship in a random spot managed to hear One (not both devices) ping for a brief period that unfortunately they didn't get to record, but had plenty of pictures of the hydrophone and stalwart rescue crew ready to share with the Chinese domestic press.

They have a Chinese media reporter on that coast guard cutter.

Quoting Aesma (Reply 275): Well the announcement weeks ago by the Australian PM that wreckage had been found really didn't help in that regard !

What? I don't recall any such announcement? Source?

Quoting jelliesR (Reply 274): how convenient that a Chinese ship in a random spot managed to hear One (not both devices) ping for a brief period

What makes you say it was a random spot? The reported location, 25 degrees South and 101 degrees East, is between the area of the Australian-coordinated search for the few days up to 3 April, and the latest search areas targetted from Friday. The location is entirely consistent with a ship which is part of the international coordinated search effort.

Edit: corrected quote attribution, which incorrectly pointed to me! a.net has some software gremlins!

[Edited 2014-04-05 17:35:28]

Quoting DTW2HYD (Reply 277): They have a Chinese media reporter on that coast guard cutter.

well of course they do. I don't mean it is convenient that they had a reporter ready, I mean the whole thing is so very convenient and the odds are so large. At least until a country hears it that doesn't have both a strong incentive to create a bit of harmless good news, and a track record of doing so.
Nobody thought to stick their phone with the record on, to the speaker, during the 15 minutes of pinging?

Quoting jelliesR (Reply 280): Nobody thought to stick their phone with the record on, to the speaker, during the 15 minutes of pinging?

I'm not sure a phone would record anything at the pingers frequency? I don't dispute that they could have done a better job of evidencing their discovery though...

Quoting jelliesR (Reply 280): well of course they do. I don't mean it is convenient that they had a reporter ready, I mean the whole thing is so very convenient and the odds are so large. At least until a country hears it that doesn't have both a strong incentive to create a bit of harmless good news, and a track record of doing so.

You have to understand Chinese position in this situation. They have lot to prove to make themselves relevant to this investigation. In general they handled aviation accident investigations through media message, or there lack of. Never released detailed accident data within the country, never proved their ability to conduct a successful investigation.

One fine morning they are competing against US, Australia and UK in solving an unprecedented mystery.

Quoting DTW2HYD (Reply 282):

the one thing that makes me mad...it 'appears' that during this 'joint search', one or more of the countries involved are more focused on 'bragging rights' of being the 'first to find' ... it appears to me that precious hrs are lost because ALL info isn't being forwarded straight to the 'search coordinators' for the 'collective' to assess....all this 'one-upmanship' (and govt 'beaurocracy') could be to the detriment of the greater cause ...ACTUALLY FINDING MH370

and its being reported in oz on ABC24 (newschannel) that the Chinese vessel is not responding to any calls to contact the search coordinators....

just my opinion as a frustrated onlooker

[Edited 2014-04-05 19:11:28]

[Edited 2014-04-05 19:14:27]

News conference at 0330Z apparently

The main question is why the Chinese would not be co-ordinating with the search taskforce? What have they got to hide?

It seems odd that they would be going it alone, if those reports are true.

I suppose the sound of the plane's pinger is easily distinguishable from that of a sub's sonar ...

I hope I'm wrong, but I have a feeling this press conference is just going to be another operational update and nothing earth shattering.

Quoting bellancacf (Reply 286): I suppose the sound of the plane's pinger is easily distinguishable from that of a sub's sonar ...

I think it's the characteristics of the ping that distinguishes it as an underwater locator beacon ping - a signal emitted on 37.5 kHz once per second.

Watching the briefing.

Angus Houston* says they have heard back from the Chinese "maritime rescue center" which confirms there were two independent detections: one on Friday (unknown duration), one on Saturday (90 seconds, within 2km of the Friday detection). HMS Echo is en route. Additionally, Ocean Shield has detected "an acoustic signal" in her current position and therefore is not leaving her current search zone.

*: I believe he is the head of the Joint Agency Coordination Center.

ETA: Additional information from Inmarsat suggests they have narrowed the search to the "southern portion of current search zone".

Updates from Q&A: Chinese signal is "consistent" with black box ULB. Estimated depth in current location of Haixun 01 is 4.5km. First detection was "night before", 36 hours ago - "quick acoustic detection and then nothing". "Haixun 01 stayed in the area", "yesterday afternoon Perth time" Haixun ("24 hours apart") heard it again 2km from original detection zone (15:47 Perth time). The Chinese acoustic event was "in the high probability area". HMS Echo will be there very soon (14 hours or so away).

Ocean Shield has found "another acoustic event" in the past 90 minutes that they are analyzing and they are trying to rule that out. Ocean Shield is about 24 hours sailing, in addition to about 6 hours to pull up and redeploy her towed pinger locator. However, Ocean Shield will not leave until mid-afternoon Perth time today at the earliest until after they evaluate the signal that they've picked up. They have no further details - specifically not the frequency - but "it's something that needs to be investigated."

Plane traveled a little bit faster and thus further on reanalysis from Inmarsat, thus is close to southern edge of current search zone. This area is close to where Haixun 01 is located. Australia found out about the first Haixun 01 acoustic events from media reports; followed shortly thereafter by official notice from Chinese authorities. Second report came first from Chinese officials to JACC. China has seven ships in area, most from any nation.

Another press conference in the "next couple of days" with more detailed maps and timeline expected.

[Edited 2014-04-05 21:12:22]

The Ocean Shield accoustic detection has only occurred within the 90 minutes preceding this press conference (so that would be approximately 0200Z).

Even if the signal dies, we have a very close generalized search area, so we know where to conduct a below the surface visual search. I'm convinced the Chinese found it...I mean what else could it be?

Conference has ended. Here are the major takeaways since I was editing my previous post and you may not have seen all the changes.

1. Three separate acoustic events they are looking at right now:
a. one by Haixun 01 on Friday night Perth time that was of a "short" duration;
b. a second event of about 90 seconds at 15.47 Saturday Perth time also by Haixun 01 about 2km distant from first detection; and,
c. a third event about 90 minutes before the start of the press conference (Sunday, about 10am Perth time) by the Ocean Shield, about 300 nm away from the Haixun's location.

2. The Haixun's events were described as being "consistent" with ULBs. There was no information about the Ocean Shield's detection yet.

3. Based on revisions from Inmarsat, the plane is more likely to be in the southern portion of the current search zone. This is where the Haixun 01 heard the pings on Friday and Saturday.

4. HMS Echo is en route to Haixun 01's location and will be there within 14 hours.

5. Ocean Shield will remain on station until at least early afternoon Sunday Perth time to investigate the acoustic event they heard on Sunday morning Perth time. If they do decide it's nothing, it will take about 2-3 hours to retrieve the towed pinger locator, about 24 hours to reach the Haixun's location, and about 2-3 hours to redeploy the locator.

6. The Australians first heard about the Friday event from media, and were informed shortly thereafter officially by China. The second event was first communicated to the Australians and then media reports broke.

Quoting davidzill (Reply 291): Even if the signal dies, we have a very close generalized search area, so we know where to conduct a below the surface visual search. I'm convinced the Chinese found it...I mean what else could it be?

You could say the same thing of the Australian detection...but at least one of them is unrelated (right?)

Quoting aviators99 (Reply 293): You could say the same thing of the Australian detection...but at least one of them is unrelated (right?)

Based on the body language, I don't think that at least the head of JACC is particularly optimistic right now, though he is determined. I'm not sure if he's being rightfully cautious or is just resigned to this being a multi-year search to even get the general location down.

Quoting Pihero (Reply 271): 2.1 - the effect of wind on drift ( change of direction of the trajectory ) and speed ( the Doppler shifts are based on ground speed,and no other is ignored, or left aside. Taking the winds aloft values for the day, provided by Tim Vasquez, the latest estimated point would have had a 230° /110 kt wind, which entails a drift of 12° left and a ground speed of 390 klt for a heading of 180°TRUE.

The inertial model I first used incorporated a 110 knot crosswind as well--it was able to replicate the 400 knot Inmarsat track exactly.

Quoting Pihero (Reply 271): (B) - A constant TRUE heading reference, which is quite unlikely as we only use TRUE reference at high latitudes -generally around 80° of latitude, North or South : We should see the effect of the winds aloft with varying ground speeds and varying courses due to the varying drifts.

Why is this, if you don't mind my asking? Why do airline pilots prefer using magnetic heading references? In the Navy we never used them, except in emergencies--which happened once or twice on my watch. Sure, we kept track of the variation and deviation, but for everyday practical purposes, we always used true headings unless the gyros were down for some reason. Heck, even when I'm out hiking, if I got a GPS that gives me true headings, I prefer that over a magnetic compass. There's a switch, the HDG REF switch, that can be set to TRUE with the punch of a button. Why is it that airliner pilots prefer magnetic headings?

Quoting Pihero (Reply 271): (C) - A constant MAG (netic) heading : here we'll see the aircraft is subjected to the wind - drift and ground speed - and the rapidly changing magnetic declinations.. To illustrate this point, imagine a MAG heading of 180° with a declination of 15°W at the estimated 20:11 locus : This means that the aircraft is in fact flying a TRUE heading of 165°, at which, subjected to a 230° / 110 kt wind, its course would be 150° and its ground speed 415 kt... That's 30° away from a TRUE 180° heading and a 35 kt slower speed.

Doesn't the 777 autopilot compensate for crosswinds? Just askin' cause I don't know....

Summary of Angus Houston's briefing here. For information, he was in the RAAF, rose to Air Chief Marshal, and then went on to head the Australian Defence Forces. Quite a 'good bloke' by all accounts:-

http://www.abc.net.au/news/2014-04-0...ysia-airlines-flight-mh370/5370558

Quoting davidzill (Reply 291): I'm convinced the Chinese found it...I mean what else could it be?

I honestly hope so, but judging from some of the technical discussion regarding the ping locating equipment it could be lots of other things to include; biological sources, operator error, equipment error, and electronic interference.

Quoting WarrenPlatts (Reply 295): Why do airline pilots prefer using magnetic heading references?

It's not that pilots prefer it, it is because the whole infrastructure is built on magnetic headings, from audio weather reports (text products use true headings for some reason) to runway numbers to VORs to charts.

The ultimate standby instrument in a plane is the whiskey compass. Even if all your electrics fail, that will still work. Many, if not most, smaller planes don't have an automated way of determining true heading since they don't have a GPS. They'll have a compass and possibly a VOR receiver. A GPS certified for navigation use in an aircraft has to be panel mounted, so it becomes quite an expense.

Pilots learn to convert headings ad nauseam once they the instrument rating and the ATP/ATPL. As aeronautical maths goes, it is not very hard. The mnemonics Cadbury's Dairy Milk Very Tasty and True Virgins Make Dull Company are practically tattooed on the inside of my eyelids by now. 

Things are changing, of course. Even a small Cessna comes with an advanced glass avionics suite as standard now, including dual GPS receivers.

Perhaps in a decade aviation will go to true headings. Very perhaps though. Things change very slowly in aviation because of the gigantic expense it takes to certify changes and propagate them. It is quite possible that aviation will stay on magnetic for a hundred more years simply because it is too much expense to change for too little benefit.

[Edited 2014-04-05 21:55:15]

[Edited 2014-04-05 21:56:29]

[Edited 2014-04-05 21:57:03]

Quoting WarrenPlatts (Reply 295): Doesn't the 777 autopilot compensate for crosswinds? Just askin' cause I don't know....

If you're in "heading" mode, it files that heading -- if you're in track mode, it maintains that track, effectively compensating for winds.

Quoting jelliesR (Reply 280): Nobody thought to stick their phone with the record on, to the speaker, during the 15 minutes of pinging?

The pinger is inaudible to the human ear.

Quoting IndianicWorld (Reply 285): The main question is why the Chinese would not be co-ordinating with the search taskforce? What have they got to hide?

There are known Chinese civil "cargo ships" in these waters as well as near guam which do not appear to conduct any normal trade. They are thought only to carry antennas and electronics and operated by the PLA-N.

It is my understanding these ships have not been tasked by AMSA.