Malaysian Airlines MH370 contact lost
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A totally speculative but possibly plausible scenario one can see, based on facts and comment cited in world press and here (from reading every current pprune thread item to this point), is that some unknown circumstance might have very rapidly put the aircraft into an high-g deep flutter mode, possibly with multiple other instabilities and spin, such that the flight crew were physically unable to move enough or to see well enough to respond with corrective control inputs.
In such situation, the instrumentation, flight and airframe sensors and perhaps also the antennas might similarly have been impaired or overloaded by vibration and rotation of the airframe to such extent that data values were beyond allowable limits or range and thus filtered or overridden in some cases.
A relatively high rotation but relatively flat spin ensuing might also have confused any remaining data-link capability to the extent of sync-loss and absolute blocking of resync signalling needed to maintain the links data transfer capability, even while the aircraft was still flying and operating in an impaired but largely intact condition.
End result of this scenario is descent to the sea at moderate velocities with or without final breakup occurring at and after first contact with the sea surface -- leaving little or no floating debris and practically none shed while airborne.
(Foregoing is all guesswork, but based on some personal knowledge and experience with all of the above. Is my attempt to add a different perspective to some of the confusing "facts" that are on the table now.)
In such situation, the instrumentation, flight and airframe sensors and perhaps also the antennas might similarly have been impaired or overloaded by vibration and rotation of the airframe to such extent that data values were beyond allowable limits or range and thus filtered or overridden in some cases.
A relatively high rotation but relatively flat spin ensuing might also have confused any remaining data-link capability to the extent of sync-loss and absolute blocking of resync signalling needed to maintain the links data transfer capability, even while the aircraft was still flying and operating in an impaired but largely intact condition.
End result of this scenario is descent to the sea at moderate velocities with or without final breakup occurring at and after first contact with the sea surface -- leaving little or no floating debris and practically none shed while airborne.
(Foregoing is all guesswork, but based on some personal knowledge and experience with all of the above. Is my attempt to add a different perspective to some of the confusing "facts" that are on the table now.)
Last edited by arcniz; 9th Mar 2014 at 13:56.
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EGLD
I don't think you need to be apologetic for asking. It is a sensitive issue and you have every right to comment on it.
I think that 1 issue with this is the amount of data that would have to be transmitted and stored. I think at anyone time there are around 10,000 airliners in the sky... Thats a lot of data. It may be that there are bandwidth and storage limits... Don't know, I'm not a techie.
The other aspect to this, though is the mis use of the information, by your employer. Its already happened with the voice recorder. You only need to go on to YouTube to hear recordings which probably shouldn't be in the public domain...but that has been released by the police or whatever. I understand the desirability of having this information available... but i personally don't want big brother looking over my shoulder every second I'm at work.
But putting this in perspective of this incident/accident... its likely all you might see would be a picture followed by nothing if the power was lost or there was a catastrophic break up. And the problem i personally have... and i can't speak for anyone else... is that incidents such as this one drive the necessity to get this technology in the FD to then "spy" on the people doing their jobs, which is then abused by employers and regulators pursuing their own agenda.
Its a delicate issue.
I'll try to be polite, because I have the upmost respect for those in your profession, but your privacy concerns should not be influencing the decision to have live video being recorded and sent back to HQ in the case of the safety of an airliner, likewise the passengers have no right to privacy in such an environment, I would argue (much like any privately owned space that's actually a public space e.g. pub, train, bus)
I think that 1 issue with this is the amount of data that would have to be transmitted and stored. I think at anyone time there are around 10,000 airliners in the sky... Thats a lot of data. It may be that there are bandwidth and storage limits... Don't know, I'm not a techie.
The other aspect to this, though is the mis use of the information, by your employer. Its already happened with the voice recorder. You only need to go on to YouTube to hear recordings which probably shouldn't be in the public domain...but that has been released by the police or whatever. I understand the desirability of having this information available... but i personally don't want big brother looking over my shoulder every second I'm at work.
But putting this in perspective of this incident/accident... its likely all you might see would be a picture followed by nothing if the power was lost or there was a catastrophic break up. And the problem i personally have... and i can't speak for anyone else... is that incidents such as this one drive the necessity to get this technology in the FD to then "spy" on the people doing their jobs, which is then abused by employers and regulators pursuing their own agenda.
Its a delicate issue.
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I wonder if any mechanics on the 777 know? This has a line drawing of the antenna positions Introduction to Antenna Placement and Installation - Thereza Macnamara - Google Books fig 3.7. And a pic of a typical elt http://www.emteq.com/cmsdocuments/EM..._Fixed_ELT.pdf
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frankly, it would clearly be beneficial to have this data being recorded and transmitted for the safety of millions of travellers every year, and if you or your passengers object to being recorded on the basis of personal privacy being put ahead of safety, one would suggest you find another job/airline
When was the last time a commercial aircraft crashed and the reason for it remained unknown? I honestly don't know. Wanting these cameras is a sign of who you are, you want instant answers, hungry to know the reason something happened even though it is in no way connected to you and will probably not affect you in any way. In time I am sure we will all know why this aircraft disappeared just as we have with many other incidents that remained a mystery for some time. Relax, it will all be clear soon and we can stop with the ridiculous knee jerk reactions like suggesting live feeds should be everywhere.
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Originally Posted by goeasy
For those critical or curious about ELT performance.... Any radio transmitter needs an external aerial to propagate the signal. Here lies the problem in ELT design.... How to have an aerial attached that won't break off or disconnect in a serious collision or explosion. And none are designed to work under water, as far as I know.
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Weather considerations
I delved a little into this in order to get some feeling for possible wind and current drifts. I found the closest stations to be Kuala Terengganu (WMKN) in Malaysia and Phu Quoc (VVPQ) in Vietnam, on both sides of the Gulf of Thailand.
During the last two days, WMKN metars show weak southerly winds with NE in the afternoons, presumably a coastal seabreeze, less than 10 knots. VVPQ reported slightly more breeze at E-SE between 3 and 12 knots.
It is of course possible that winds in the middle of the gulf, where MH370 vanished, are different, but my guesstimate for the area is for light to medium winds from the E-S sector. Which would have kept any debris from an in-flight breakup in a reasonable area, and pushed any debris and oil on the surface in the direction W-N.
Perhaps someone can dig out some upper level wind charts from the area for the last two days. This might help in guesstimating the debris spread from any in-flight breakup at cruise level.
During the last two days, WMKN metars show weak southerly winds with NE in the afternoons, presumably a coastal seabreeze, less than 10 knots. VVPQ reported slightly more breeze at E-SE between 3 and 12 knots.
It is of course possible that winds in the middle of the gulf, where MH370 vanished, are different, but my guesstimate for the area is for light to medium winds from the E-S sector. Which would have kept any debris from an in-flight breakup in a reasonable area, and pushed any debris and oil on the surface in the direction W-N.
Perhaps someone can dig out some upper level wind charts from the area for the last two days. This might help in guesstimating the debris spread from any in-flight breakup at cruise level.
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No speculations there
As for the AF447 the locating beacons (ELT) failed miserably in their mission
This is ridiculous to not have some in external location instead in the aircraft
There are also aboard ships and they are not located in the bilge !
It is now hoped that the CVR and FDR pingers will work
As for the AF447 the locating beacons (ELT) failed miserably in their mission
This is ridiculous to not have some in external location instead in the aircraft
There are also aboard ships and they are not located in the bilge !
It is now hoped that the CVR and FDR pingers will work
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<<Nobody seems to have addressed the question of how did those with the stolen passports enter Malayasia – if in transit at KUL from Thailand, how come that Thai exit immigration did not pick up on the stolen passports? Thailand issues entry visas, which should have expired in both the stolen passports. If they were already in Malaysia, where are their photos and fingerprints that Malaysian Immigration take for all arrivals? >>
Perhaps they entered Malaysia using different, valid passports.
Perhaps they entered Malaysia using different, valid passports.
I suspect there are many more reasons to travel on a stolen passport than terrorism. Especially if your destination is in Europe: What do the immigration people do with those that arrive on stolen passports? Can they return them? Where to? If the "refugees" don't cooperate, immigration will never know where they're from, thus can't ship them back. Apply for asylum and hope you can establish a foothold. That's how economic migration to Europe works these days as far as I know anyway, happy to stand corrected.
The fact that they were travelling to the same destination (if that's true) and that they bought sequential tickets on CSN, all that proves is that those two probably had something to do with each other. Perhaps they were both from the same family. It would be interesting to see some stats on how many illegals arrive at AMS every day.
The fact that they were travelling to the same destination (if that's true) and that they bought sequential tickets on CSN, all that proves is that those two probably had something to do with each other. Perhaps they were both from the same family. It would be interesting to see some stats on how many illegals arrive at AMS every day.
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Why are you not pushing for mandatory cameras to be installed in private cars?
"We" have decided that we need to know minute details of what is said on an airliner, so it's clearly beneficial. To have this data at least updated remotely as the flight takes place would clearly be of huge benefit, would it not? so why wouldn't video of the cockpit be of even more benefit?
I don't want to derail this thread, I probably should've sought out the no doubt other threads on this subject, but felt I wanted to comment on the privacy issue
The technicalities of whether it's possible are irrelevant if we can't get past the privacy issue
Thanks for the considered responses though, unlike the PM
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It is of course possible that winds in the middle of the gulf, where MH370 vanished, are different, but my guesstimate for the area is for light to medium winds from the E-S sector. Which would have kept any debris from an in-flight breakup in a reasonable area, and pushed any debris and oil on the surface in the direction NW-N.
Perhaps someone can dig out some upper level wind charts from the area for the last two days. This might help in guesstimating the debris spread from any in-flight breakup at cruise level.
Perhaps someone can dig out some upper level wind charts from the area for the last two days. This might help in guesstimating the debris spread from any in-flight breakup at cruise level.
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"Interpol might be helpful but the issuing organisation is the best source of information. Could probably also pick up differences in photos in the passport quickly as well."
I suspect this isn't the thread for deep discussions about that, but certainly with today's technology one could get a "fingerprint" of the original image, a comparable scan "fingerprint" and a scan of the person presenting the document with AI processing in the background. If one has advanced TX of bookings/manifest that is even easier. No doubt someone has calculated the cost of implementation/ongoing operation is more than the notional loss of airframe/lives. Plus if one has this everywhere, it is harder to infiltrate or exfiltrate assets one wants to slip in for whatever reason. A lot is "security theatre" or carefully restrained implementation.
I suspect this isn't the thread for deep discussions about that, but certainly with today's technology one could get a "fingerprint" of the original image, a comparable scan "fingerprint" and a scan of the person presenting the document with AI processing in the background. If one has advanced TX of bookings/manifest that is even easier. No doubt someone has calculated the cost of implementation/ongoing operation is more than the notional loss of airframe/lives. Plus if one has this everywhere, it is harder to infiltrate or exfiltrate assets one wants to slip in for whatever reason. A lot is "security theatre" or carefully restrained implementation.
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For a more in-depth primer on radar horizon calculations in a variety of units, see Computing Radar Horizon
The aircraft wouldn't have to lose very much height at that distance before it dropped below the radar horizon for a land based radar site at 200Nm out. Nevertheless, I'm confused - why can they not say 'it was travelling at [x] knots on vector [y] at rate of descent [z] before it vanished from our scopes'? That's what military radar installations are there for, surely?
The aircraft wouldn't have to lose very much height at that distance before it dropped below the radar horizon for a land based radar site at 200Nm out. Nevertheless, I'm confused - why can they not say 'it was travelling at [x] knots on vector [y] at rate of descent [z] before it vanished from our scopes'? That's what military radar installations are there for, surely?
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"This is ridiculous to not have some in external location instead in the aircraft"
External ELT antennas exist. Can't speak for the implementation on the MAS777's. See p.8 http://www.honeywell.com/sites/servl...5-F0579B51DCEA
External ELT antennas exist. Can't speak for the implementation on the MAS777's. See p.8 http://www.honeywell.com/sites/servl...5-F0579B51DCEA
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There's specialzed hydrophones to locate the pingers. http://www.phnx-international.com/sp..._SpecSheet.pdf
Deptrai, I hope they're using the "specialized hydrophones" to locate the pinger. The French nuclear sub, looking for AF447 didn't! That's why they went back to review the sonar tapes of that sub. Don't know if the dynamic range of the tapes would have recorded 40khz anyway.
Deptrai, I hope they're using the "specialized hydrophones" to locate the pinger. The French nuclear sub, looking for AF447 didn't! That's why they went back to review the sonar tapes of that sub. Don't know if the dynamic range of the tapes would have recorded 40khz anyway.
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The last point of contact with the aircraft might not be the point of break up, if indeed that happened..... It may have travelled 90 degrees to the last known direction whilst/if the crew had time and attempted a recovery... That was part of the issue with AF447... It had turned 180 degrees from the original track by the time it hit the water, i understand
MH370 does not seem to have sent any ACARS data. ACARS is self powered. Meaning that is like earlier poster mentioned, he would pull fire handles and switch battery off in less than 10sec, ACARS would still send coordinates and vital aircraft data.
This means that MH370 got either destroyed immediately, which on AF447 was not the case, or MH learned from AF447 incident and keeps the ACARS data for themselfs.
Has it become the norm for military and civilian radars to capture and store the data at high resolution for playback?
Unless it is, it would be asking for a lot to have a military radar operator pay attention to an undistinguished blip at long range during the small hours of the morning.
Unless it is, it would be asking for a lot to have a military radar operator pay attention to an undistinguished blip at long range during the small hours of the morning.
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B 777 Electrics
There was mention earlier about the various electrical systems on some of these aircraft. A simplified version of many of the airliner systems is available on the web.
B777 Electrical
http://www.smartcockpit.com/aircraft...Equipment.html
These are for study purposes and are generally 'dumbed down' versions of the schematics found in the engineering and crew training manuals.
They do give a good indication of the system layout you would expect to be seeing though.
B777 Electrical
http://www.smartcockpit.com/aircraft...Equipment.html
These are for study purposes and are generally 'dumbed down' versions of the schematics found in the engineering and crew training manuals.
They do give a good indication of the system layout you would expect to be seeing though.
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Because private cars aren't carrying 300 people
A live video would not be of much benefit, what are you recording? The backs of two guys/girls, would the definition be good enough to see instrument indications? The only reason for this would be to know the plane has crashed, not why. We know the plane has crashed as it did not land. Sound recording is already there, not live but we will know soon enough and that is far more valuable than a video of a cockpit environment without much definition. The benefit would be far outweighed by the cost and misuse by companies.
Lets focus on something sensible when the findings are found. Spend the money on better identity checks, training, maintenance or whatever it is deemed caused this sad event rather than ludicrously expensive high definition multiple live feeds from every possible angle of an aircraft in flight. Its the knee jerk reactions that make everyones life harder, not safer. How am I safer not being able to take nail scissors onto an aircraft when I can purchase a large glass bottle full of flammable liquid to take on the flight with me? I could smash that bottle over someone, set them on fire and stab them. I am all for implementing better security and surveillance measures if they make sense but live camera feeds are not it.