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LandSweetLand
Posts: 185
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:02 pm

Quoting Dalavia (Reply 195):
Apparently the location of the unconfirmed ping is 25 degrees South, 101 degrees East.

That's pretty far north compared to where they were initially looking.

Quoting nupogodi (Reply 198):
Oh, gosh, am I going to have to be eating my hat?

Better get one of those Nacho ones just in case.

[Edited 2014-04-05 05:06:05]
 
wjcandee
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:03 pm

[turn skeptic ON]

I didn't know the Chinese ship HAD a "ping detector"

[turn skeptic OFF]
 
noflies
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:18 pm

Quoting LandSweetLand (Reply 200):
Quoting Dalavia (Reply 195):
Apparently the location of the unconfirmed ping is 25 degrees South, 101 degrees East.

That's pretty far north compared to where they were initially looking.

They're definitely a long way from initial search, but it looks like it's in the south of today's planned search area.
http://www.jacc.gov.au/media/releases/2014/april/mr009.aspx
 
LandSweetLand
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:20 pm

Quoting noflies (Reply 202):
They're definitely a long way from initial search, but it looks like it's in the south of today's planned search area.

Thanks for that link. I didn't know they were looking that far north already.
 
noflies
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:29 pm

Quoting LandSweetLand (Reply 203):
Thanks for that link. I didn't know they were looking that far north already.

Makes me wonder what new information they have. If you look at the search areas to date, there are areas along the arc that they seem to have skipped over to have ended up so far north - way north-west of Perth!

Still, this isn't yet an official report from the Joint Agency Coordination Centre, and I'm a tiny bit skeptical this early in the media release, considering the source and the timing. Yes it's a pinger frequency, but is the report true? No idea.

For the sake of the families and friends, I sure hope this is something substantial.
 
noflies
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:35 pm

Link to Xinhuanet media release.

(Link removed, sorry - it was the wrong link)

[Edited 2014-04-05 05:59:16]
 
CBRboy
Posts: 181
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:51 pm

Quoting noflies (Reply 205):
Link to Xinhuanet media release.

http://news.xinhuanet.com/english/china/2014-04/04/c_133239044.htm

9:20am Beijing time = Perth time, so plenty of time (the whole day) for the Joint Agency to do a media release. Think that's odd?

Your link is to a Xinhua story on Friday afternoon Beijing time which says that Haixun 1 has arrived in the northern search area. The Xinhua story about the ship detecting pings is timed at 19:23 Beijing time on Saturday.

[edit] Most interesting is that yesterday's story says the water depth in that area is 5000 meters. Isn't this beyond the range we have been told in early threads that the pinger could be detected?

[Edited 2014-04-05 06:01:36]
 
ltbewr
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:52 pm

Let us hope the possible sensing of the 'pinger' is true and leads to the recovery of the recorders from MH370. I do fear that the Chinese government may have prematurely disclosed this without verification for political reasons, to look good to the world but also to try to give some possible info to the victims especially as the largest number of pax on the flight were PRC citizens.
I am concerned though with the Chinese lack of following proper investigative procedures so far seen. From the premature disclosure of possible debris that were just usual garbage, not using gloves handling possible debris, does challenge the impartiality of the investigation.
 
noflies
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 12:58 pm

Quoting cbrboy (Reply 206):
Your link is to a Xinhua story on Friday afternoon Beijing time

Apologies, I'll remove the link if I can!

The time you quoted, in that case, makes more sense in terms of why no media release from the Joint Agency.

[Edited 2014-04-05 06:00:47]
 
coolian2
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:05 pm

If this isn't true, China become just as culpable as anyone else in terms of lying to the media.
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LandSweetLand
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:08 pm

Someone (apparently a CCTV presenter) on twitter is claiming their sources say that it was only detected for 15 minutes
https://twitter.com/jameschau/status/452425439126892544
 
noflies
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:17 pm

Quoting LandSweetLand (Reply 210):
Someone (apparently a CCTV presenter) on twitter is claiming their sources say that it was only detected for 15 minutes
http://twitter.com/jameschau/status/...92544

What could explain that?

[Edited 2014-04-05 06:18:29]
 
CBRboy
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:21 pm

Quoting ltbewr (Reply 207):
I am concerned though with the Chinese lack of following proper investigative procedures so far seen. From the premature disclosure of possible debris that were just usual garbage, not using gloves handling possible debris, does challenge the impartiality of the investigation.

Perhaps you could explain further what you think the Chinese Government has done wrong here. As I recall, the Vietnamese authorities announced they had located objects in the sea, as have Australian authorities (based on satellite photos) on more than one occasion. None of these resulted in anything confirmed to have come from the plane. A previous poster was already prepared to critcise China for delay in releasing this news. Personally I think we should welcome the news, surprising as it is!  

[Edit]One reason the pinger might have been detected for only 15 minutes would be if the detecting ship had moved past the black box at the edge of the pinger's range and wasn't able to relocate it after turning round.

[Edited 2014-04-05 06:27:40]
 
WarrenPlatts
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:27 pm

Quoting wjcandee (Reply 197):
Of course, the Chinese agency could be totally wrong about this info. If true, an amazing stroke of luck

Actually, it's right on the last "ping arc".

 
panampaul
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:34 pm

Here is a link to a short story about the Chinese announcement.

China Reports ‘Unidentified’ Ping in Southern Indian Ocean
Signal Not Confirmed to be from Malaysia Airlines Flight 370


Quote:
As the presumed deadline for locating the black boxes or flight data and voice recorders from the ill-fated Malaysia Airlines jetliner looms, searchers are reporting a possible signal from the plane.

The government-run Xinhua news agency is reporting that a Chinese ship with a black-box detector picked up an “unidentified” pulse Saturday that came from the designated search area in the southern Indian Ocean.
 
coolian2
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:34 pm

Can I just say, in defence of CNN, Richard Quest is genuinely outstanding.

You can tell he cares about aviation and wants it reported right.
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spacecadet
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:38 pm

Quoting ltbewr (Reply 207):
I do fear that the Chinese government may have prematurely disclosed this without verification for political reasons, to look good to the world but also to try to give some possible info to the victims especially as the largest number of pax on the flight were PRC citizens.

It may turn out to be another red herring, but I can't see how it would make China "look good" to intentionally release info that turns out to be false, and they would know that. There has to be at least something to this; they have to at least be sure that they heard something and that it's on the right frequency.

The problem is now they're reporting they only heard it for 1.5 minutes, not 15 (according to Sky News, who's translating a Chinese report). That seems a little strange, but they could have been on the very edge of the pinger's range and might not know which direction it was coming from.

Hopefully we will hear more about this soon, and hopefully it turns out not to be another dead end.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
 
art
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:44 pm

Quoting LandSweetLand (Reply 210):
Someone (apparently a CCTV presenter) on twitter is claiming their sources say that it was only detected for 15 minutes

At least that is a series of pings. Reports were saying that a ping had been heard without making clear that it was not a single ping.

It is very umlikely that the ship would have detected the last 15 minutes of pings emitted. If this not a false positive and IF the pings were really at the right frequency, could it that the beacon is in a trench (more like a dip in reality) where the signal stopped being received because it fell below the horizon due to the ship's movement? Or simply that the ship moved far enough away from the beacon that it went out of detection range?

[Edited 2014-04-05 06:58:27]

[Edited 2014-04-05 06:59:31]
 
sipadan
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:48 pm

Quote:
=Sipadan]=And, I'm sure the investigation, a month in, has the same dearth of information that we have, and therefore has no basis whatsoever in calling this a CRIMINAL act.
Quoting Pihero (Reply 191):
Yes, you are correct.

I think it's asinine to believe that the actual investigation only knows what the general public at large knows.That's an incredible statement. The amount of copious information and data alone that they (the investigative team) are privy to dwarfs what has been released publicly (as is the nature of a criminal investigation). I'm flummoxed at how you can make this assertion?

Quoting nupogodi (Reply 198):
Oh, gosh, am I going to have to be eating my hat? That'd be incredible if true...

My hat is in the ring with yours on this one. I am VERY skeptical about the validity and accuracy of this, but it is state media. Fingers crossed, but man, what a stroke of luck (blind OR otherwise).
 
ranold76
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:52 pm

If there has been any trend in this ordeal, when hearing "new news," be prepared to be disappointed.
Hopefully this is the location, so many answers can be given to the many questions.

[Edited 2014-04-05 07:04:37]
 
MD11Engineer
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 1:59 pm

It is quite unlikely that there are several unrelated ULBs currently active in this area, so if they can confirm the reception, it could only come from the B777.
Secondly, sound propagation in sea water depends a lot on water temperature and salinity (which affect the water's density). At boders between various layers of water sound can by reflected and directed. Submariners have known about these effects since many decades and used them to hide from detection.

As for a detector, all one needs is an underwater microphone sensitive at the correct frequency, and amplifier and a frequency converter (also used e.g. as a bat detector). These are not particularly hightech items and the Chinese should have a few of them as well. Also remember that the Chinese Navy has submarines aned faces a threat from enemy submarines, that they'll have to have such equipment.

Jan
Je Suis Charlie et je suis Ahmet aussi
 
SimonDanger
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:02 pm



Quoting spacecadet (Reply 216):
It may turn out to be another red herring, but I can't see how it would make China "look good" to intentionally release info that turns out to be false, and they would know that. There has to be at least something to this; they have to at least be sure that they heard something and that it's on the right frequency.


Perhaps I can add some perspective to this particular news item. I am on record in some early threads saying I was curious as to China's lack of any material role in this investigation. China is a full-on command and control communist country, and nothing that comes out of China happens either accidentally or by individuals. Nothing. This is by design. It is perfectly logical to see China throwing this out in the waning days of the FDR/CVR pinger batteries to save face with the family and relatives of flt. 370, showing China as having contributed the most significant development to date, only to have the search drift into obscurity after another two weeks of nothing else. I will happily rescind my remarks and give props to the PRC if I am proven wrong, but this just has all the markings of a manipulative government trying to manage the message rather than the problem, as always. If something makes China look good, you can rest assured that it was intended to.



[Edited 2014-04-05 07:04:45]


[Edited 2014-04-05 07:07:24]
 
EBGflyer
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:08 pm

I find it highly unlikely they would find pings from the aircraft before finding debris. Debris would be scattered around at the surface and probably at a large area much more likely to find than a ping, which anymore listening would have to be in very close proximity to in order to pick up.

Just try to recall how long it took finding AF447 after finding debris and having a pretty good location as to where to search. With MH370 they still have no idea where to search exactly and considering the vast search area I find it highly unlikely they would get lucky and pick up a ping. Seems more like the Chinese are eager to get the news out that things are being done, but to me this just make the whole search and rescue effort seem unprofessional - at least the PR side of it.

[Edited 2014-04-05 07:10:43]
Future flights: CPH-BOS; CPH-SVG; CPH-PVG-HKG-MNL-DVO; CPH-CDG; CPH-NRT; CPH-MIA; CPH-PVG
 
Pihero
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:09 pm

Quoting sipadan (Reply 218):
I'm flummoxed at how you can make this assertion?

I ddidn't;.
You did. (See the quote ?).

Quoting sipadan (Reply 218):

I think it's asinine to believe that the actual investigation only knows what the general public at large knows.

Hence that gives fuel to wild assumptions of cover-ups and conspiracies. Hmmmm !..   

Quoting sipadan (Reply 218):
The amount of copious information and data alone that they (the investigative team) are privy to dwarfs what has been released publicly

Cite some infos and data... i.e Facts
Contrail designer
 
by738
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:15 pm

Quoting EBGflyer (Reply 222):
I find it highly unlikely they would find pings from the aircraft before finding debris

Didnt someone suggest that this site was similar to one of the "field of debris" sites ?
 
comorin
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:21 pm

Quoting Pihero (Reply 223):

Touche, mon ami! D'Artagnan would be proud.  
 
hoya
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:22 pm

Quoting EBGflyer (Reply 222):

I find it highly unlikely they would find pings from the aircraft before finding debris. Debris would be scattered around at the surface and probably at a large area much more likely to find than a ping, which anymore listening would have to be in very close proximity to in order to pick up.

It's possible that any meaningful debris could've sunk by now.

BBC article states that three different people on board the ship heard the ping, but that it wasn't recorded (really?!). So it either is China saving face, or it is a very credible lead (wouldn't this cause searchers to concentrate searching in this area?) but the Chinese just didn't think about having a recorder of some sort.

http://www.bbc.com/news/world-asia-26902127

Quote:
China's Liberation Daily reported that three people on board had heard the signals, which were not recorded as they came suddenly.


[Edited 2014-04-05 07:22:23]

[Edited 2014-04-05 07:23:23]

[Edited 2014-04-05 07:24:06]
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slinky09
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:23 pm

Quoting EBGflyer (Reply 222):
Seems more like the Chinese are eager to get the news out that things are being done, but to me this just make the whole search and rescue effort seem unprofessional - at least the PR side of it.

Am I the only one who is somewhat bored by the "Chinese find debris", "Chinese satellite sees debris", "Chinese hear ping" etc. I suspect lots of state controlled media eager to send out a particular message ... instead, until there's one shred of actual evidence, a real ping or something else, it remains unproven where the plane is.
 
MD11Engineer
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:24 pm

Quoting EBGflyer (Reply 222):
I find it highly unlikely they would find pings from the aircraft before finding debris. Debris would be scattered around at the surface and probably at a large area much more likely to find than a ping, which anymore listening would have to be in very close proximity to in order to pick up.

By now debris on the surface will have moved quite a distance from the original crash site.
As for the reception, conditions under water can actually guide the sound farther away than normal and they are varying all the time. If the ship was just at the edge of the reception zone, it is quite possible. Aniother thing is that the ship was probably not actively searching, but transiting to a new assigned search area and had their locating equipment on, just in case.
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mandala499
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:42 pm

Quoting PlaneInsomniac (Reply 24):
In the case of Adam Air 574, most of the plane has not been found until today.

They found it along with the blackboxes... but they did not recover most of the wreckage.

Quoting DJM18 (Reply 166):
It provides some valuable perspective for those of us interested in the aircraft's turn around Indonesia, which I presume would be the brown (as best I could describe that color) and purple rings.

It seems consistent in the initial stages with going along E92 along the FIR border of Jakarta and Colombo.

Quoting BackSeater (Reply 104):
- pre-compensation is implemented by the Honeywell 4200/7200 satcom modem via method b). I believe that modem was on MH370. Can anybody confirm?

This calculated pre-adjustment based on the ARINC 429 feed is what almost everyone making Inmarsat aero equipment use. Where the ARINC 429 feed is not available, you replace the source of the feed with a satellite reference unit (mini IRU dedicated for the orientation and accelerations), and a magnetometer (for the compass), and the GPS receiver within the antenna, or another GPS position source.
When losing situational awareness, pray Cumulus Granitus isn't nearby !
 
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Tugger
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:48 pm

Please correct me if I am wrong but the CVR only records the last 30 minutes and then records over itself, while the FDR will keep a much greater timeline of data.

Tugg
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solarflyer22
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:52 pm

Quoting coolian2 (Reply 215):

Can I just say, in defence of CNN, Richard Quest is genuinely outstanding.

Yeah he is. It seems unlikely to me that they would find it so quickly though. A graphic I saw earlier said they can only cruise at 1-5 knots while searching otherwise they'll miss the ping. That's very slow given the area they have to cover.

Unless they spotted on satellite where the plane crashed weeks ago and didn't tell anyone, I doubt how this could be accurate. It would be an amazing stroke of luck.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 2:59 pm

Quoting tugger (Reply 230):
Please correct me if I am wrong but the CVR only records the last 30 minutes and then records over itself, while the FDR will keep a much greater timeline of data.

CVR on this flight, 2 hours loop as reported by lots of different media outlets.

FDR on this flight, apparently 25 hours but I've heard of FDRs recording more than 50 hours so I don't know.

edit: The 30min you mention is a legal minimum I believe. Not sure which authority prescribes it... But have heard from multiple sources that 30min is the bare minimum to be legal.

[Edited 2014-04-05 08:00:42]
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Backseater
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 3:29 pm

Quoting mandala499 (Reply 229):
This calculated pre-adjustment based on the ARINC 429 feed is what almost everyone making Inmarsat aero equipment use. Where the ARINC 429 feed is not available, you replace the source of the feed with a satellite reference unit (mini IRU dedicated for the orientation and accelerations), and a magnetometer (for the compass), and the GPS receiver within the antenna, or another GPS position source.

Fine. So you concur that pre-compensation is implemented per ICAO+Inmarsat Aero specs. The a/c has all the info needed to negate its Doppler contribution in the direction of the satellite. Then what are the physical sources of the Doppler measurements shown on the Inmarsat/AAIB Doppler 450kts chart? The companion chart states:

Quote:
D2 is a combination of the Doppler components due to satellite motion, which is accurately known, and the aircraft heading and speed. Using the burst frequency offsets measured at the land earth station, it is possible to compare against the aircraft heading and speed.


I still don't understand how they can have it both ways!
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 3:47 pm

Quoting BackSeater (Reply 233):
Then what are the physical sources of the Doppler measurements shown on the Inmarsat/AAIB Doppler 450kts chart?

The movement of the aircraft relative to the satellites nominal position is compensated for by the terminal. This assumes a perfectly geostationary satellite. It is not. The movement of the satellite relative to the ground station is compensated for. This leaves a tiny Doppler shift which is uncompensated for, the movement of the satellite relative to the aircraft.
A man must know how to look before he can hope to see.
 
flymia
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 3:48 pm

Quoting nupogodi (Reply 232):
CVR on this flight, 2 hours loop as reported by lots of different media outlets.FDR on this flight, apparently 25 hours but I've heard of FDRs recording more than 50 hours so I don't know.

Can't both be turned off by pulling the circuit breakers? Obviously that will tell us a lot if they were shut off.
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WarrenPlatts
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 3:48 pm

If you want to calculate the LOS velocity of the aircraft away from the satellite, it's simply:

LOS speed = BFO * c / 600,000,000

Divide the LOS speed by the cosine of the altitude to get the radial velocity from the subsatellite ground position.

E.g., if the BFO is 250 Hz, then the radial velocity from the subsatellite point is approximately ~320 knots. If the aircraft crossed the last ping arc at 400 knots near where the Chinese ship supposedly heard the pings, then that would indicate a course/heading of about 156.

Which indicates (a) the aircraft probably was not on autopilot, and (b) if the pilot was lost, since it was daylight at that point, he should have been steering east--not south by southwest....

Conversely, if the pilot was lost, and was steering due east, that would entail that the azimuth from the satellite to the plane was 054, which would place it on the 00:11 LOP over Yunnan Province in southern China....

ETA: If you'll recall, I was able to deduce the radial velocity from the subsatellite point for the last ping ring LOP (00:11 UTC) from the published Inmarsat tracks. The velocities were virtually identical down to 4 significant figures. Then I did the same analysis on the 22:40 UTC ping ring and got radial velocities for both tracks of 280 knots. Then, as an experiment, I took the published Doppler shifts of 250 and 200 Hz using an "effective frequency" of 600 MHz. The predicted radial velocities were within 3% of the measured radial velocities.

Thus, the published BFOs by Inmarsat must all be precorrected, and by assuming a frequency of 600 MHz, one can get the same radial velocities used to construct the Inmarsat flight paths.



[Edited 2014-04-05 09:12:18]
 
zanl188
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:05 pm

Quoting nupogodi (Reply 232):
CVR on this flight, 2 hours loop as reported by lots of different media outlets.

FDR on this flight, apparently 25 hours but I've heard of FDRs recording more than 50 hours so I don't know.

edit: The 30min you mention is a legal minimum I believe. Not sure which authority prescribes it... But have heard from multiple sources that 30min is the bare minimum to be legal.

Not to mention the quick access recorder. QARs are typically used for maintenance purposes but frequently helpful for accident investigation.
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nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:08 pm

Quoting flymia (Reply 235):
Can't both be turned off by pulling the circuit breakers? Obviously that will tell us a lot if they were shut off.

Dunno. CVR/FDR breakers have been pulled before, but images of the 772 breaker panel posted here ages ago did not show a breaker specifically for CVR or FDR. Couldn't tell you more, really.
A man must know how to look before he can hope to see.
 
nupogodi
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RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:08 pm

Quoting zanl188 (Reply 237):
Not to mention the quick access recorder. QARs are typically used for maintenance purposes but frequently helpful for accident investigation.

QARs are not crash-proof, so good luck
A man must know how to look before he can hope to see.
 
Summa767
Posts: 1847
Joined: Thu Mar 11, 2004 1:30 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:09 pm

Quoting LandSweetLand (Reply 210):
Someone (apparently a CCTV presenter) on twitter is claiming their sources say that it was only detected for 15 minutes

The CCTV reporter onboard the Haixun-01 said that the signal was detected for 15 minutes on Friday, and then again Saturday (today), for only 1 minute and a half.
They were not too confident on Friday's signals as there were other ships in the area and they thought that it could be interference. However, hearing this signal again today, albeit for a short time, has clearly made them more confident as shown by release of the information.
 
nupogodi
Posts: 933
Joined: Mon Mar 10, 2014 10:58 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:12 pm

Quoting Summa767 (Reply 240):
they thought that it could be interference

I struggle to think of any interference that would be registered as an intermittent pulse at the exact frequency.

Sure would be amazing if this was it, though. Still going to take a while to get the proper submersibles to the area, though...
A man must know how to look before he can hope to see.
 
WingedMigrator
Posts: 1771
Joined: Wed Oct 26, 2005 9:45 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:21 pm

Quoting DJM18 (Reply 166):
The order of rings is:

brown 18:29 UTC
purple 19:40 UTC
green 20:40 UTC
pink 21:40 UTC
red 22:40 UTC
white 00:11

Point of order: we only have the last ping ring from Inmarsat. The other colors are quite pretty, but calculated based on unknown assumptions.
 
Backseater
Posts: 478
Joined: Fri Aug 19, 2005 3:20 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:29 pm

Quoting nupogodi (Reply 234):
This leaves a tiny Doppler shift which is uncompensated for, the movement of the satellite relative to the aircraft.

Yes but in that case, as I explained before, the satellite motion gives you directional information regarding the a/c but almost nothing about its speed and heading. Besides the Doppler values would not be as large.

The measured data seems to behave as if AES pre-compensation was not kicking in. Maybe the AES does not compensate its transmitted RF unless it is getting close to the maximum acceptable Doppler limit at the satellite (>300Hz).
 
WarrenPlatts
Posts: 517
Joined: Wed Mar 26, 2014 6:03 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:36 pm

Quoting WingedMigrator (Reply 242):
The order of rings is:brown 18:29 UTCpurple 19:40 UTCgreen 20:40 UTCpink 21:40 UTCred 22:40 UTCwhite 00:11Point of order: we only have the last ping ring from Inmarsat. The other colors are quite pretty, but calculated based on unknown assumptions.

The thing is, the measured radial velocities for both Inmarsat tracks at DS's 20:40 are the same ~280 knots, derived by measuring the headings and azimuths to the satellite GP.

Meanwhile, yesterday, I was operating on the assumption that the next LOP was at 23:11--not 20:40. When I did the radial velocity calculation for a hypothetical 23:11 LOP, the radial velocities did not match very closely. That tells me that the Inmarsat folks actually were using the same ping rings given at duncansteel.com--they can be trusted IMHO.
 
zanl188
Posts: 3800
Joined: Sat Oct 21, 2006 9:05 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 4:45 pm

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

Regardless, they have been used for accident investigations. And if all you find is the QAR....
Legal considerations provided by: Dewey, Cheatum, and Howe
 
panampaul
Posts: 229
Joined: Wed Jan 23, 2013 4:01 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 5:02 pm

Australian officials said they are considering moving "assets" to the site where the Chinese ship picked up the ping.

Quote:
Australian officials said they are considering moving Royal Australian Air Force “assets” to the area where the signal was detected

above from
China Reports ‘Unidentified’ Ping in Southern Indian Ocean

.
 
Kaiarahi
Posts: 1810
Joined: Tue Jul 07, 2009 6:55 pm

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 5:30 pm

Quoting sipadan (Reply 247):

A few words of advice, since you've only been on a.net for 3 weeks. There are some very respected members on here, who have earned that respect through years of demonstrating their knowledge and expertise as aviation professionals. Pihero is one. They're generally happy to explain and debate - in a reasoned way. Many of us are happy to learn from them. Unfortunately we have lost others (including a flight test engineer extremely knowledgeable about 777 systems, who could have contributed immensely to this thread) because they simply became tired of being insulted and treated with disrespect. 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.
Empty vessels make the most noise.
 
User avatar
ssteve
Posts: 1436
Joined: Fri Dec 02, 2011 8:32 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 5:36 pm

Ahh, the ever useful BBC provides the rough location of the possible FDR pinger "pulse" detection on a map:
http://news.bbcimg.co.uk/media/image...rliner_search_624_05.04_signal.gif
In this article:
http://www.bbc.com/news/world-asia-26902127

[Edited 2014-04-05 10:43:33]
 
vvbkumar
Posts: 39
Joined: Mon Jun 23, 2008 11:39 am

RE: MH370 Malaysia Airlines B772 Missing Enroute KUL-PEK Part 50

Sat Apr 05, 2014 5:50 pm

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.
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