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-   -   Malaysian Airlines MH370 contact lost (https://www.pprune.org/rumours-news/535538-malaysian-airlines-mh370-contact-lost.html)

VH-Cheer Up 9th Mar 2014 23:01

447 hit the water at 10.912 ft/min = 124 mph. It went in almost flat pitched up about 16 degrees. The discussion here was about a nose-first trajectory to come up with a time of 40 seconds and a final speed in excess of 800 kt

Lady Pterodactyl 9th Mar 2014 23:07

This is all desperately sad for everyone involved. It just seems so very similar to BOAC Flight 781 - the De Havilland Comet 1 crash off Elba. In that instance there was no apparent surface wreckage from the airframe but unfortunately the bodies of some of the passengers did stay on the surface. I don't envy the SAR teams their job one little bit.

Ditchdigger 9th Mar 2014 23:12

Since speculation in some of the last few posts has included mention of speeds in the supersonic neighborhood, I'll ask a question that's been on my mind--Has there been any mention anywhere of reports of a sonic boom? How far across open water might one be audible?

Lantern10 9th Mar 2014 23:16

For what it's worth, the two passengers travelling on the stolen passports were booked to fly out of Beijing and on to Amsterdam later that day.

Missing Malaysia Airlines plane: What happened to MH370?

tartare 9th Mar 2014 23:18

Have read through the previous posts - both informed and speculative.
All very puzzling.
The following questions meant in no way to distress, or cast aspersions on MH.
Fair to say that modern airliners usually only vanish during the cruise for one reason.
If there was an explosive device, then why no sign of a flash from IMINT satellites? I assume that thousands of pounds of Jet-A1 vapourising, even at that altitude would create some kind of instantaneous flash - or is a breakup in the cruise possible with no accompanying fire - I suppose it is?
And as yet, no revelations of primary radar trace of large parts of structure falling?
IIRC, one positive comment often made about the 777 is that it's a very strong air-frame. Even at circa 0.84 mach, air loads that might induce a catastrophic structural failure would surely still see large pieces left as part of the break-up sequence?
And no debris field yet.
Very strange.

HIALS 9th Mar 2014 23:22

ACARS?
 
ACARS is not mandatory equipment. Aircraft can dispatch under the MEL with inop ACARS.

The information posted here so far does not categorically state that the ACARS was working prior to the event. The information I can see indicates that 'no failure messages were received' etc...

Was the ACARS operating normally prior to the event?

jmmilner 9th Mar 2014 23:28


Submarines to search? :rolleyes: sure, the sonar may yield something but it's got to be a WTF moment here!
Modern submarines are the best mobile platforms available for detecting sounds in the ocean. The whole front of a sub is a giant array of microphones coupled with major computing power all riding on a platform that itself is designed to be ultra-quite. AF447 included a French nuclear submarine in the initial search for the black boxes.

SalNichols94807 9th Mar 2014 23:28

Why no flash detection?
 
Probably because none of the three operational birds are looking for missile launches or nuke detonations in Malaysia.

WillowRun 6-3 9th Mar 2014 23:30

Tokyo's (Rosy) Convention
 
@andrasz

Thank you; Sir. I understand that the legal scheme you described is what exists.

But the present legal system is set up from the inside looking out. That is, each nation state has its own system of identity controls and verification. And of dealing with all the fine-point particulars noted alluded to or otherwise mentioned on-thread. And from this, sort of like the UN, set of each nation taking its own approach (no pun intended), the international system is constructed. It looks from the inside (each nation) out (to the international, world-wide, global order of civil aviation).

That's why we have a "conflict" between the state of registry and the situs (legal word for, "place", one that is "formally identified by or with a juridical structure") where PIC's inherent legal authority is exerted in fact. In my legal opinion the ICAO governance system not only should be changed, but it MUST be changed so that the situs law yields to the authority of the PIC as articulated by such Captain's "rank" in the overall global civil aeronautics sector. It's a concept of "the legal right of way". The system needs to be re-done, looking from the outside (the global system perspective) in (into each country).

And as with collaring a stinking drunk, ordering my brother the rabbi to finish his prayers later and get in his seat (and belted) and so on and so forth - the civil aeronautics system globally has to impose some order on the apparent Swiss cheese paradise of passport laxity.

I was a student radical in the era of the SDS. Posters need not waste their fingers telling me 'things can't be changed'. I'm on the ORD perimeter - happy to chat over a brew with any and all four-stripers, oh and surely yes, I'm buying.

SalNichols94807 9th Mar 2014 23:32

You understand that shallow water is a very difficult acoustic environment for a submarine, right?

RobertS975 9th Mar 2014 23:36

Mid-air theory is bogus, and so is the bomb scenario at FL 350... there would be a debris field that would have been discovered by now. This plane hit the planet intact.

andrasz 9th Mar 2014 23:48


2014, not capable to find a plane...
You cannot find something until you start looking at the right place. In this case, we only have the last known position, but theoretically the plane might be anywhere within a 5000km radius. OK, you can cross some areas off where you can certainly tell it isn't, but still its a huge area. In this case search starts from last known position, then goes outwards in expanding circles.

We do have very sophisticated remote sensing technology, but for that to work it also needs to be zoomed in to a small 'area of interest'.

sdelarminat 9th Mar 2014 23:49


RobertS975 Mid-air theory is bogus, and so is the bomb scenario at FL 350... there would be a debris field that would have been discovered by now. This plane hit the planet intact.

Anybody remember how was the Alaska MD found? It hit the water nose first, was there too much debris, or was it difficult to find if it wasn't for the witness pilot reporting its position?

golfyankeesierra 9th Mar 2014 23:49


I am afraid you misinterpreted my post or deliberately tried to show your self-proclaimed ACARS "knowledge" to this community disqualifying my statement
@barrelowl: I see a lot of uninformed comments here, including yours:

I conclude that the ACARS downlink feed from the aircraft completely stopped at some point
How do you know there is a "downlink feed"? In my airline if all is ok there is only an engine trending downlink around TOC and nothing else for the rest of the flight.
How does it work at MAS? I have no idea, do you?

fg32 9th Mar 2014 23:52

Fastest possible descent rate? People have been asking….
 
For those keen to discuss shortest possible time of descent, and hence to assume a full throttle vertical dive, we can calculate very crudely, incorporating air resistance, thus:

Thrust to weight ratio of similar aircraft is given at about 0.2 to 0.3. Assume one third.
(A ratio of 1 would mean that sustained vertical climb was achievable).
So if the engines are achieving a certain stabilised speed in level cruise, then pointing the nose vertically down will in effect add three times as much thrust, due to gravity, giving four times the thrust.

The new stabilised speed will be such as to counter this 4 fold increase with 4 times the drag. Since drag increases with the square of speed, the speed will double.
So, very very crudely, the aircraft will stabilise its descent (terminal velocity) at twice its horizontal cruise speed.

We are ignoring:
A bit faster if we assume zero angle of attack (not actually flying).
And of course the air thickens on the way down, slowing us, and we should be talking actual speed, not IAS.
And the engine performance will presumably reduce in these conditions.

However, for these crude purposes I think we can say that the engines cannot drive us down vertically much faster than twice the speed they can drive us horizontally.

I don't think anyone is suggesting that this was in fact the mode of descent, just trying to get some idea of the fastest method imaginable.

Remember, very crude, ball park only. But it strongly suggests you can't get down vertically as fast 3 or 4 times cruise by running the engines.

And ignoring, of course the supervening break-up into slower falling bits

Not sure such a question is really very relevant, but the scenario intrigued me once posed, and I had to fiddle.

(Physics and math post grad, for my sins, so I shouldn't really do this in case I c**k it up, but I don't think it's wildly wrong)

Mr Optimistic 9th Mar 2014 23:55

Oh, and when do the wings come off ?

Toruk Macto 9th Mar 2014 23:57

Hats of to the governments and military of these countries to allow so many other countries to send in ships and planes . Let's hope the right equipment can be working in the search area ASAP no matter where its from .

areobat 9th Mar 2014 23:59


BEA offers assistance

French accident board offers help recovering missing flight MH370


"We have communicated to Malaysian and Vietnamese authorities that we are ready to assist with the underwater search operations or recovery of wreckage," a spokeswoman for the Paris-based BEA accident investigation branch said on Sunday.
Isn't this the same group that couldn't find AF447?

tartare 9th Mar 2014 23:59

Sal - are you sure?
The NYT is quoting a source specifically saying that systems designed to pick up such flashes have not done so.
I would have thought that the whole of South East Asia would have been a prime area for the US DOD to be looking for flashes, given the proximity to at least three nuclear armed states, and others who have ambitions to be?
The two SBIRS birds in orbit are geostationary, and I would assume have sensitive enough detectors with wide enough fields of view to pick up a fuel-air explosion at that height and location?
Particularly given that it was dark at the time?
My apologies - it seems those satellites operate in highly elliptical orbits, so might not have seen any explosion - if there was one.
Returning to the topic now, and thinking of the relatives of those who are missing...


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