[Editor’s note: One of the most intriguing clues in the MH370 mystery is the fact that the airplane’s satcom system logged back on to the Inmarsat network at 18:25. By understanding how such an event could take place, we can significantly narrow the range of possible narratives. In the interest of getting everyone on the same page in understanding this event, I’ve asked Mike Exner for permission to post the content of a detailed comment he recently provided. One piece of background: a lot of us have been referring to the satellite communications system aboard the aircraft as the “SDU,” but as Mike recently pointed out in another comment, it technically should be called the “AES.” — JW.]
Until we have more evidence to support the theory that the loss of AES communications was due to the loss of primary power to the AES, we must keep an open mind. Loss of power may be the most likely cause (simplest explanation), but the fact is we do not know why the sat link was down between 17:37 and 18:25. My reluctance to jump to the conclusion that it must have been due to the loss of primary AES power is based on decades of experience in the MSS (mobile satellite service) industry. It’s not just another opinion based on convenience to support a theory. Let me elaborate on a few possible alternative explanations.
The potential for loss of the pilot carrier, due to the orientation of the aircraft in relation to the satellite, was increased as soon as the airplane turned WNW. Between the time of this turn (circa 17:50) and the time of the FMT (final major turn circa 18:25-18:40), the aircraft was flying more or less toward the satellite where the antenna pattern was near a null. Don and I have both looked at the antenna pattern in some detail and concluded that the antenna pattern and coincidental direction of flight were unlikely to be so bad that the pilot carrier would be lost due to this geometry. Moreover, according to a MAS Press Conference on March 20, 2014, there should have been an ACARS message transmitted at 17:37, but none was received. ( bit.ly/QFbF6C ) At 17:37, the aircraft was still over Malaysia SW bound, so the HGA pattern would not have been an issue at that point. Taken together, loss of the pilot carrier due to antenna orientation appears to be a possible, but unlikely explanation for the outage.
Ionospheric scintillation has also been suggested as a possible explanation for the loss of service during this period, but there have been no reports of other aircraft in the vicinity suffering a loss of service, so this explanation is also unlikely. (Note: Ionospheric scintillation in the equatorial regions can be a big problem for VHF and UHF communications, but it does not affect communications in the L band as much.)
The MCS6000 AES, located in the back of the airplane, requires a continuous feed of INS data (position, speed, etc.) via an ARINC 429 link from the computers in the front of the plane. If the AES stopped receiving INS data for any reason, then it would not have been able to steer the HGA, or compute the required Doppler corrected transmitter frequency. Thus, it is very likely that the AES would be out of service if there was any loss of this 429 data link, or the information carried over the link. Given that there was no VHF voice communications after 17:19:24 and the Transponder Mode S data was lost after 17:21:13, it is certainly possible that the INS data flowing to the AES was disrupted due to a common failure in some piece of equipment in the E-Bay. This explanation for the loss of service cannot be dismissed as easily as the two previous theories.
However, there is one additional observation that tends to favor the loss of primary power theory over the loss of INS data theory (or the other two theories above). We note that when the AES logged on at 18:25:26, the BFO values for the first few minutes thereafter appear to have been drifting in a way that is more consistent with a restoration of primary power event than a restoration of INS data event. If the AES power had been on during the outage, the oven controlled reference oscillator would have maintained a stable frequency and there should not have been any significant BFO transients following the 18:25:26 logon.
In summary, there are multiple alternative explanations for the AES outage, but loss of primary power is the most likely explanation. Like so many other necessary assumptions, like the mode of navigation after the FMT, we have no choice. We must base the search on the most likely assumptions while maintaining an awareness that few of the assumptions have probabilities of .999.
In case the AES was disabled by isolating the left power bus, and then it came back online when power was restored at 18:25, that must not necessarily have been done for the purpose of communication. What other systems would have been brought back to life through that action?
@el_gato: It’s possible that left power bus was isolated in order to cut power to AES w/o leaving the cockpit, but this would require a very savvy operator, as Boeing doesn’t make it easy for you to figure out what’s connected to the left AC bus. It took the IG a lot of collective rooting around before Bill Holland was able to dissect a 777 training manual and put a spreadsheet together. Long and short, there doesn’t appear to be any piece of equipment that you’d need to isolate the entire left AC bus to shut off, which would take out the AES as a collateral effect.
Excuse my ignorance, but isn’t the a/c equipped with a master circuit breaker to shut all systems down in case a of catastrophic electrical fire?
@jeffwise:
Suppose the left AC bus was isolated for whatever reason, and at 18:35 the culprit discovered that he needed a system powered by that bus?
@gysbreght, Only a very, very sophisticated hijacker would have any clue what systems are powered by the left AC bus. When Mike went to run his simulator trials in early November, the pilots running the simulator (very knowledgeable and experienced guys) didn’t even know you could turn the AES on and off this way.
And if a crew member calls to the Captain we’ve got smoke coming out of the e-bay. What happens then?
Do they flip CB’s to the e-bay?? Or are those systems fire safe?
@jeff,
thanks for replying, but have you answered el-gato’s question? Or, if for some reason you don’t want to answer it, is there perhaps reason to consider it?
Airlandseaman,
You say: “Given that there was no VHF voice communications after 17:19:24”.
Was not the captain of the aircraft bound for Narita able to establish contact shortly after 17:30 via VHF? Not informative, though.
Oleksandr:
Perhaps someone else can answer definitively. My understanding is that the report you refer to has never been verified. The last official VHF communications was at 17:19:24 (“Good Night Malaysian Three Seven Zero”).
Airlandseaman,
I presume there is no reason for the pilot of Narita bound airplane to make such a false claim. If so, VHF was likely functional by 17:30. How would this affect your conclusions?
A long time ago, someone posted (maybe here, maybe on PPRuNe or Duncan Steel’s site) that the LH AC Bus powers the cabin pressurization control system. I do not know if that information is accurate or not.
I believe I read that the B-777 compressed air for the cabin comes from a bleed off of the compressor section of the engine and the B-787 uses electric compressors.
@airlandseaman, Oleksandr:
You are correct. Has not been verified. And this is one possible reason why:
The ORIGINAL version of the 03.09.14 NST article reporting this story (which I cited in a 05.16.14 post on Duncansteel) specifically mentioned MH88. That flight number was subsequently scrubbed from the NST piece. You can’t even find it in the Wayback machine.
This pprune poster cites that same now- scrubbed NST piece and data from FR24 suggesting that the anonymous pilot was from MH88: http://bit.ly/1yRLz3u
Jeff,
Excellent concise title of this thread. Thanks for bringing this topic for discussion.
It is one of the key questions that made me doubt about FMT “as is” in the combination with the AP hypothesis, and consider other scenarios.
But we pretty much know there was someone on this plane switching things off, and all about the same time. Factor the log on frequency characteristics Mike refers to and it looks irresistible – to me. Someone did that.
Lauren H:
My understanding is that there are both valves and compressors powered by the Left AC Bus, and a redundant set of valves and compressors powered by the Right AC Bus. So isolating the Left AC Bus by itself would not cause depressurization. Don recently did some research for me on this question. Perhaps he will chime in and explain this in more detail. I’m not sure what the valves do if the AC Bus is isolated. They probably maintain the current state, whether open or shut.
It should also be noted that it is not necessary to isolate any Bus to depressurize the airplane. If that was something someone wanted to do, there were much easier ways to accomplish that goal.
Airlandseaman,
A question a bit out of the topic.
You say: “It should also be noted that it is not necessary to isolate any Bus to depressurize the airplane. If that was something someone wanted to do, there were much easier ways to accomplish that goal”.
I just recalled my earlier discussion with Bobby whether crew could do anything in case of onboard smoke event. Wouldn’t such a depressurization at low altitudes be a life-saving solution?
Hi Oleksandr ~
Here is the original New Straits Times article. It did not specify flight MH88 or any other flight number. MH88 was a speculative guess that became an unconfirmed internet rumor and still exists as a stubborn urban legend:
https://www.evernote.com/shard/s460/sh/2272dd1e-c82f-44a6-8e91-a59586f21c29/80d6aa358eaea5bed105155f40a54581
Also, please note the additional information from the PPRuNe forum that I presented below the original NST article.
~LG~
Just FYI:
This is the DS post I referenced previously, wherein the NST article (referencing MH88) was cited:
http://www.duncansteel.com/archives/763/comment-page-1#comment-4556
I’ll just submit that Duncan Steel would very likely not have approved a post that inaccurately cited information from an article on which the post was based.
@Oleksandr ~
Here are the tweets from three respected journalists who, upon reading the original New Straits Times article, began to question which flight the pilot was commandeering. If the article had specifically stated that the flight was MH88 they would have had no need to speculate, nor would anyone else:
https://www.evernote.com/shard/s460/sh/726579a8-dd38-4a90-8f5e-b3a45547d2bc/6ab57f44e5ee0065a179c3cd743a3586
~LG~
Could an unstable reference frequency from the oven controlled reference oscillator have been able to cause the data corruption on the 18:25:34 & 00:19:37 BTO Login Ack values? Inmarsat declared these values are unreliable delay and are an artifact of internal channel/frequency switching within the satcom terminal. I am just curious could an unstable oscilllator frequency have had any effect to cause some sort of signal distortion or interference on the these partial handshake signals and if so could these Login requests BTO values on these time events 18:25:27, 00:19:29 have also been affected? Please read:
http://www.thehuntformh370.info/content/my-response-inmarsat-garbage-question
Ken S
@jeffwise
“Only a very, very sophisticated hijacker would have any clue what systems are powered by the left AC bus”
It is likely that access to a good flight simulator would allow a not-so-sophisticated hijacker to figure out a lot of the systems connected to the bus.
A trial and error discovery would allow him/her/them achieve all hijack objectives (e.g. comms out, door lock disabled, etc.).
Cheers,
Will
Ken: These were not “partial handshake signals” circa 1825. They were a complete login packet sequence. The only so called partial handshake signals occurred at 001929 and 001937.
Moreover, the reference oscillator was not “unstable”. It appears to have drifted slightly in the first few minutes, but it was not unstable (irratic). In EE lingo, these terms have a very different meaning. The apparent drift is consistent with an oven oscillator that was turned on circa 1822, after a period of being powered down for more than 10 minutes.
@Oleksandr ~
Please refer to two posts from Tim Farrar’s blog contained in the following note titled “MH370 ~ Correcting The Record On MH88”:
https://www.evernote.com/shard/s460/sh/fdcebdcf-498d-48a1-af3d-580012edda6e/278d14f2e762fd75207e1e4f88836e6b
These posts were recorded on May 2, 2014 and May 3, 2014 respectively. For the record, they are no longer valid. At that time I had made the error of accepting an unconfirmed internet rumor as fact without conducting the appropriate in-depth research needed to reveal that the information was without merit. Since that time I have discovered my initial assumption was incorrect. I stand by my current research. I welcome any proof that MH88, or any other flight, made contact with MH370. I doubt anyone will find such evidence but I would be extremely pleased to be proven wrong. Any information that will bring truth to the MH370 saga is most welcome.
~LG~
This doesn’t bode well.
MH370: ocean search falls behind schedule
DANIEL STACEY THE WALL STREET JOURNAL JANUARY
THE hunt for the remains of Malaysia Airlines Flight 370 is falling behind schedule as the lead contractor, an oil and gas firm with little experience in searching for deep-sea wreckage, battles issues with its equipment and bad weather.
Fugro NV has struggled to acquire and fit its ships with sonar capable of operating at extreme depths in a remote part of the southern Indian Ocean, where investigators believe the plane went down last March with 239 people on board.
The Dutch firm negotiated with other companies to quickly acquire the necessary deepwater sonar devices after the Australian government awarded it the $52 million search contract on Aug. 6, but its first search ship wasn’t able to begin sonar scans until late October, more than a month behind the government’s agreed-upon start date.
Once deployed, the ship battled high seas and suffered technical glitches that have limited its search to around 60 days up to now.
Problems with acquiring and installing other sonar systems slowed the deployment of a second search vessel for months. And compounding the troubles, a tropical cyclone recently suspended the search for several days.
An Australian government spokesman said authorities are “satisfied with the quality of the search data” from Fugro and that vessels were operating in accordance with contract arrangements.
Fugro, which has been searching alongside a Malaysian-contracted vessel, said its equipment is “best in class.”
“We have carefully followed the tender procedures and have responded with what we believe is the best combination of capability and reliability,” Rob Luijnenburg, a company spokesman, said.
Australian authorities expected searchers to be nearly halfway done by now with their underwater exploration.
Instead, searchers have covered less than a third of the deep-sea area.
Even if all had gone as planned, the result may well have been the same. Despite a previous massive international search effort, no piece of debris from the plane has ever been found.
But the current delays have drawn criticism from Australia’s political opposition party, industry experts and a family member of two victims, who question why Fugro was chosen over more-experienced firms that already owned deepwater sonar equipment.
“What was the point of selecting a company that is not equipped to do the search? Isn’t that a waste of time?” asked Sharil Shaari, a family spokesman for Norli Akmar Hamid and her husband, Muhammad Razahan Zamani, who were travelling on Flight 370 to Beijing for a honeymoon.
Australia has said it wants Fugro to complete the bulk of its operation in the 60,000-square-kilometre search zone by May, but experts privately say they believe that goal may be unattainable, or that the search may be rushed and not completed to an industry standard.
Even when sonars are fully operational, the equipment Fugro chose only provides scans of the ocean up to around 1200 metres wide, compared with a more-typical range of 3,000 to 6,000 metres often used by navies and salvage experts to search for lost planes and ships, these experts say. The thinner scan width means searchers may be unable to overlap their scans sufficiently in the time left for the search and ensure they don’t miss any wreckage.
“I am very concerned about these findings” of delays and other problems, said Anthony Albanese, the opposition Labor Party’s spokesman on transportation. “We need to ensure that there is a positive outcome in this search.”
Australia’s government accepted overall responsibility for the Flight 370 hunt last year as a gesture of regional friendship, and because the main search area is best accessed from the Australian coast. It budgeted up to $90 million for the operation, and has said its expenditure will be split with Malaysia. China has provided limited support, including the use of some ships, because many of the passengers on the Beijing-bound flight were Chinese citizens.
Malaysian and Chinese officials have not commented on Fugro’s struggles.
Further delays could test Australians’ willingness to keep paying, especially if May passes without any sign of the plane or if more funding is needed. Martin Dolan, chief commissioner of the Australian Transport Safety Bureau that is coordinating the search, has already said the current budget may only allow searchers to scour around 80% of probable crash sites, which were determined after months of analysis of radar, satellite and aircraft-performance data by international experts.
The Australian government spokesman declined to speculate on what would happen if searchers don’t find any part of the plane by May.
Malaysian and Chinese officials likewise wouldn’t offer specifics on potential next steps for the search.
Underwater searchers are relying on deep towed sonar devices on cables up to six miles long to scour the ocean floor. Industry experts say only a few firms around the world have experience in carrying out such searches, which in this case involves rugged terrain, including deep crevasses.
Australia’s choice of Fugro surprised many in the industry.
“There are people who have better experience with their equipment,” said Paul-Henry Nargeolet, who led efforts that found Air France Flight 447 in 2011 — the last major jetliner to go missing in deep water. “If Fugro is spending half their time fixing their problems — that’s not good.”
Mr. Nargeolet didn’t bid for the Flight 370 contract.
Australia hasn’t released the amounts of the competing bids. Under the terms of the tender, the government wasn’t required to select the lowest bidder. The government wouldn’t comment on why it chose Fugro.
The company has extensive experience in running lengthy ocean operations with rotating crews and multiple vessels — key aspects of the search.
The company also is considered a global expert at ocean-floor mapping for oil and gas projects and cable surveys, and routinely operates at depths of up to two miles. But parts of the Flight 370 search zone are significantly deeper, reaching up to three miles down, at depths in which just a few companies in the world have experience operating.
Fugro began its underwater scans in late October — missing the government’s request for a September start — after acquiring and installing equipment rented from the Taiwan firm Dragon & Elephant Enterprise on the first ship, the Fugro Discovery. The ship has continued to struggle with rough seas, and the equipment has also suffered technical issues.
Mr. Luijnenburg, the Fugro spokesman, said the company also ordered new sonar systems manufactured by Edgetech, Inc., of Massachusetts, for the firm’s second search vessel. One system didn’t arrive on dock in Perth until January, he said.
Others arrived earlier, but couldn’t be deployed on the second vessel, the Fugro Equator, because cables and winches that operate them couldn’t be installed. That kept the second ship, originally slated to join the search with towed sonar in mid-September, out of commission until Jan. 15.
Fugro recently added a third ship to bolster the search operation.
The GO Phoenix, another vessel hired by Malaysia using a team that had been unsuccessful in bidding through the Australian tender, was able to begin searching by Oct. 5, working under Australian authority. Apart from minor technical glitches and weather disruptions, the GO Phoenix has searched successfully since then. Australian authorities would not compare the progress of the GO Phoenix to Fugro’s three ships.
Australia’s contract for the search drew bids from many of the world’s specialist sonar operators, including Oceaneering International Inc., a Houston-based firm that helped locate the Titanic at a depth of nearly 2 ½ miles.
“The world-wide deepwater industry is simply wondering how the contract could have been awarded the way that it has been,” Michael Williamson, president of Seattle-based sonar firm Williamson & Associates, wrote in a Sept. 15 letter to the Australian government that was reviewed by The Wall Street Journal. Fugro is ill-equipped and is likely to fail, the letter claimed.
Williamson bid for the Flight 370 contract as part of a consortium involving Oceaneering International and salvage firm Svitzer, a subsidiary of A.P. Moller — Maersk Group.
Paul Kennedy, Fugro’s Perth-based manager, dismissed criticisms from other firms as “sour grapes.”
WSJ
Having had a think about it, I would be very surprised if the Australian govt did not undertake to finish the job irrespective of any delays or overruns. Just means a drawn out search.
@Matty, I suppose it will depend on how much pressure they get from the public. Bear in mind, by the way, that it’s impossible to “finish the search.” The best they could do would be to match the boundaries of a search area that were arbitrarily set. If they do that, and still haven’t located the plane, the public (and family members especially) will forever wonder whether they would have found it if they had just kept looking for one more day…
Assuming that the plane is largely disintegrated and probably well scattered would it make sense space these runs out a little for the sake of coverage. It’s inconceivable that they could miss it if it was there with the gear they have?
I’d seriously doubt the plane is intact but I’ve heard before now that if it was, a normal bathy survey can detect it? The spot they need to hit may in fact be quite large?
@Matty, The WSJ article which you so awesomely posted says that the seabed scan width is 1200 meters; via Twitter Mike Chillit indicated that the ship tracks are 1.2 statuatory miles apart and trending wider. From the one seabed image that the ATSB released, the resolution looks extremely good, I think that they would be able to detect even a single piece of debris. So perhaps they’re banking on the debris field being wide enough that it wouldn’t entirely disappear in gaps between the scans. My gut feeling, though, is that this approach is quite wrong: I’d rather have a small area about which we can say, “There is definitely nothing here,” that a large area about which doubt lingers.
Perhaps I’m simply misunderstanding the situation and they really are covering the entire area. I hope so.
@jeffwise:
” I’d rather have a small area about which we can say, “There is definitely nothing here,” that a large area about which doubt lingers”
I recall similar thoughts being expressed by the Fugro spokesman before they started the search.
Hi LGHamiltonUSA, Nihonmama.
Thanks for your comments. I think ATSB has a definite answer whether this communication via VHF really took place or not, regardless MH88. ATSB report does not mention this issue at all, but Wiki formally cites NST. So this statement was never retracted. Perhaps Brock should add it into his list of questions to ATSB.
On 10th Feb I am going to a lecture on the MH370 search by a Fugro representative. Will post a report on what was said. What’s the key question that should be asked?
http://www.imarest.org/policy-news/newsroom-press/item/1160-imarest-stanley-gray-lecture-mh370
Re: 1:30 emerg freq comm between 370 and Narita-bound 777 pilot: I think I’m siding with Oleksandr: I haven’t seen any evidence presented here that would cause me to doubt that this pilot told the truth. Why are we to be skeptical – because it conflicts with what the Inmarsat data indicates? Doesn’t EVERYTHING?
@Brock: I’m skeptical that this supposed radio call really tells us anything, even if it really took place; as I understood it, what the Narita-bound pilot heard was static and mumbling. Why should we assume that the static and mumbling came from MH370? There is lots of static and mumbling on VHF radios everywhere, all the time.
@Richard Cole, That’s fantastic. Could you ask how far apart the search lines are, and what the range of the equipment is? (in other words, are they intentionally leaving some areas un-imaged in order to cover a wide area?) Are they using the AUV primarily to explore holes, shadows and gaps in the other ship’s coverage? When do they estimate they’ll finish, and how much will they have covered when they’re done? Having completed a given area, what percentage chance would they assign to the probability that the wreckage is NOT in that area?
In a very unfortunate turn of events, the Malaysian Inspector General of Police (IGP) ordered the police to investigate a Twitter user for suggesting the MH370 accident was a conspiracy and not an accident.
http://www.themalaymailonline.com/malaysia/article/igp-orders-probe-on-twitter-user-for-suggesting-mh370-conspiracy
We debate here about the validity and interpretation of the Inmarsat data. On the other hand, Malaysia has the following evidence in its position that could help make a determination about the Inmarsat data. This evidence includes:
1. The complete, unredacted satellite logs, including all the payload data. Only signaling data has been released.
2. All raw primary radar data, with attribution to specific radar sites.
3. The complete, unredacted ATC recordings, including any communications between Kuala Lumpur and Ho Chi Minh City, Bangkok, Singapore, and Phnom Penh, and between civil ATC and the RMAF.
4. The complete cargo manifest, including a detailed list of items that were consolidated as a single line item.
The Malaysians consistently act as if they have something to hide and then over-react to charges of impropriety.
@Oleksandr ~
You’re very welcome. Yes, it would be a great if an agency of the official investigation would confirm that no aircraft ever made contact with 9M-MRO (MAS370/MH370). And I will share one last point for you to consider, a comment that was emailed to me by a trusted technical expert who is closely involved with searching for the aircraft: “[There was] no reason for Malaysia area control to start asking crews to contact MH370 until at least 17:38, if not 17:41 when it establishes with VATM’s HCM area control that FIR handover didn’t complete.” That simple statement makes logical sense to me and so I have concluded that the NST’s claim that contact was made “just after 1:30am” does not seem to fit the official timeline. Referring to the MH370 preliminary report (Serial 03/2014), “Actions Taken Between 01:38 and 06:14 On Saturday 8 March”, it wasn’t until 02:53:51 that “MH386 was requested by HCM to try to establish contact with MH370 on Lumpur radar frequency. KL-ATCC then requested MH386 to try on emergency frequencies as well.” In closing, I’d be grateful if you would kindly keep me informed of any new information you might m receive on this subject matter. Thank you!
@Brock ~
Have you come across any information that the New Straits Times is “in the back pocket” of Putrajaya? Here in the USA we have a problem with our mainstream media outlets being criticized for acting as lapdogs for the current Administration. I’m wondering if Malaysia’s ruling regime has the luxury of being able to manipulate their media outlets, too.
~LG~
Mike,
If the handshake at 18:25 was a complete handshake then why did Inmarsat have to release a statement correcting this BTO value along with the value at 00:19?
On both these handshakes the Login Ack signals was measured erroneoisly so they had to use the derived values from the Login requests messages on these time events.
Please refer to the ATSB SUL released on Dec23 and my blog which explains this in detail. Clearly these were not complete handshakes like the the first login request at 15:59
Ken S
@jeffwise
Thank you for bringing the AES logon/logoff events to the forefront of the current discussion.
Perhaps it was known that the AC bus would make the AES go dark, but unknown that it would also lock them in the cockpit?
@mike
Thank you as always for taking the time for such a technical and professional response to my question.
Those of us in the third camp (peanut gallery) sincerely appreciate all of the energy that both the IG and other crunchers have dedicated to the cause, and hope that it helps lead to a resolution for all those affected by this tragedy.
@Orion
>Perhaps it was known that the AC bus would make the AES go dark, but unknown that it would also lock them in the cockpit?
Or, perhaps it was known that the AC bus would foolproof the cockpit, but unknown that it would cause the AES to go dark (or was indifferent to it).
Ken:
The 1825 login sequence was complete in every respect. Nothing was “measured erroneously”. All the measurements were accurate. Inmarsat and others, including me, have explained the 4600 usec correction numerous times, so I won’t repeat it again. It happens on every login. It is normal. It is not an issue. Just apply the correct bias for the channel, and all the observations make sense.
@spencer
Touché. Very logical indeed, as Occam grins.
The timing of the logon is just too uncanny.
Right after the FIRs and right before the FMT(s)??
If you read my blog and check your facts you will clearly see that the BTO value for the Login Ack on this time event (18:25:34) was measured erroneously (51000us)
This was not a normal or complete handshake
http://www.thehuntformh370.info/content/my-response-inmarsat-garbage-question
@Anyone
http://www.meriweather.com/flightdeck/777/aft/break-r.html
While trying to educate myself on the CB’s & control switches on the 777 I found these. Notice the AIMS-R (Airplane Information Management System) two 25 amp breakers. Then below AIMS-L. R designating Right, L designating Left. These AIMS breakers are in both on the maintenance CB panels. Along with GPS & other comm., systems ATC, Comm VHF, ILS, etc. And what I’m getting at is….I’ve been at this since 7:00 AM this morning trying to prove that popping CB’s could have “Blacked Out” the plane w/o a great amount of expertise.
@Chris Butler: The panels shown in that graphic are the overhead maintenance panels in the cockpit. The 3 CBs for the AES are in the E/E bay.
@VictorI
Oh…I thought the cb panels were behind them. When ya click on the overhead it doesn’t show any cb panels.
Thanks
@Chris: If I am not mistaken, it is overhead and a bit to the rear. There are pictures available that show the exact placement in the cockpit. It would take a bit of time to find that link.
@Richard: thanks for offering to relay questions; here are mine (supplemental to Jeff’s; highest priority first):
1) Why have we yet to see a single photo from any Fugro ship (the lone photo Jeff references was from Go Phoenix)? Can they please provide a RANGE of photos, so as to CONFIRM max operating scan DEPTH and WIDTH?
2) What, exactly, went wrong with Equator’s cable installation during transition to the towfish at end October? It reduced 2014 “ship-months” of searching from 8 to 6, and explanations have been extremely vague.
3) Have Fugro ships been asked to look for or document for posterity the location or character of anything on the sea floor OTHER than MH370? If so, by whom, and for what?
4) To date, the only place searched OUTSIDE the ATSB-prescribed “highest priority” zone is directly westward. Can Fugro confirm a) this was at the ATSB’s request, b) if so, why they asked for this, and c) whether they are aware of anything that might help predict the NEXT such shift?
5) Why isn’t it more efficient to RELAY crews, supplies and fuel to the 4 search ships, rather than having them spend 50% of their time in either port or transit? (Likely there’s an obvious mitigating factor, which I’m just not yet seeing.)
@VictorI
http://www.runwaygirlnetwork.com/2014/07/22/will-industry-address-vulnerability-beneath-the-carpet-of-the-777/
“The systems in the E/E bay vary from fuse panels to the Airplane Information Management System (AIMS), also known as “the brains” of the aircraft. AIMS provides flight and maintenance crews all pertinent information concerning the overall condition of the airplane, its maintenance requirements and its key operating functions, including flight, thrust and communications management, according to Boeing’s description. Also in the E/E bay are several tanks containing oxygen connected to the flight crews’ masks.”
Not sure if “communications management” would include the AES or not.
@LGH, @Jeff, @Victor: if I blindly trusted Malaysian media or authorities, I would be a hypocrite. Power corrupts us ALL.
So I of course join you in your skepticism, and I of course join the IG in demanding release of the data elements Victor lists.
In the same spirit, I ask the IG to join me in asking that we run to ground the many, MANY aspects of the SEARCH which haven’t added up, either.
A wise person recently pointed out that yet another run around the [redacted] signal data mulberry bush (FSDMB) is pointless, and that best next step is to shake the tree, in hopes something falls out.
So I ask us to agree to set aside any and all conflicts among our deeply worshipped pet theories (differences which I predict will some day reduce to a simple question of who was covering for whom), and SHAKE THE TREE TOGETHER.
With all our might.