I think you somewhat misunderstand the situation. Parts of the South China Sea are claimed by all surrounding countries. Last known location was in international waters, so all nations having a territorial claim frantically sent off vessels to join the chase and "show the flag" to demonstrate that the area is (in part) theirs. I'm afraid in SE Asian politics taking advantage of such a situation is considered fair game.

You're presuming that there was: a) an explosion, and b) that if there was an explosion that it met the intensity, duration, and wavelength criteria to not be rejected as noise.

Tartare, I think that a fuel explosion from a ruptured wing would certainly be picked up as it would be larger than a missile exhaust plume which is what those satellites are looking for.

But...it is difficult to imagine a plausible scenario that ends with an ignition of a ruptured wing tank. Well, its not, but I will leave that to the speculatti.

Perfect nosedive, engines off? How fast?
 

And of course, we can extend my previous crude argument to an engines-off perfect nose dive. The thrust provided by the weight will be three times that previously provided by the engines, giving a descent 1.7 (square root of 3) times faster than speed in level flight.
So the engines wouldn't really add much (1.7 to 2)
Once again, presumably break-up would supervene, making it all academic ?

I think some basic googling will help you there.

Happy for someone to provide some corrections , but I think you will find they only send data when the tag pops off, or the shark is at or near the surface.

Again electromagnetic waves don't go so well under water. (frequency dependence aside)

There are all sort sof 'add ons" that could be made to aircraft to enhance the "findability" in case of circumstances such as this. But it comes down to a cost analysis of what actual advantage you get in the rare circumstances that these things happen versus the pain in the @rse of setting them up.

Ships will need to call in to port to re supply , equipment sent from not so friendly countries will be shipped to HCM . Information needs to be shared amongst the many countries taking part in the search . International waters or not its a recipe for a lot of tention in this part of the world . Generals of all nations will be looking to protect their interests or press for advantage . It appears like cooperation is happening and long may it continue . What's going on behind the scenes is another story .

Australopithecus - you sound like you know what you're talking about.
Could you elaborate a bit more please?
My assumption was that a catastrophic airframe break up would see fuel lines and tanks ruptured, fuel vaporised and that with hot engine cores in close proximity, some sort of flash fire albeit very brief, very similar in IR signature to a rocket exhaust plume, would happen, which is why I wondered aloud.
But then I suppose it may be possible that air frame failure at 0.8 mach might just generate a lot of large pieces, depending on the modes of failure and the breakup sequence.

Just to keep the humanity here, in among the tech discussion:

Danica Weeks anxiously waiting for news of husband on missing Malaysia Airlines flight - ABC News (Australian Broadcasting Corporation)

Tartare...thanks. Its an illusion.

As someone else already mentioned the satellite data is filtered for characteristics, otherwise there would be a flood of data from lightning, gas flares, fireworks etc. But I believe, based on an article years ago, that the data stream can be retroactively inspected without the filters.

WRT to tank rupture/ignition. It takes a lot to get jet fuel to ignite...atomisation, lots of heat etc.. Cruise speed at FL350 would present a much smaller possibility of ignition than speeds, pressures and temperatures typical in landing accidents.

As SalNichols94807 commented, shallow water makes for a notoriously difficult acoustic environment. People familiar with the (wider) geographical area have stated on here that those waters are chock full of fishing vessels. Man made noise and natural noise in the water adds to the ambient noise, which will be much increased over that of an open ocean environment. Reverberations will be rife. There will be surface reflections and bottom bounce (depending what the bottom is made of). In deep water, sounds spread spherically, greatly dissipating the intensity. Shallow water, constrained by the surface and sea bed, causes the sound to spread cylindrically, meaning in a given volume the noise is greater. It's logarithmic and I can't be 4rsed digging out my old notes! 10Log versus 20Log.

That said, the shipping noise is low frequency whereas sonic locators on Flight Data Recorders is not. I hope the frequency will not be discussed. Ambient noise is still a factor.

In the Air France 447 case, the location was open ocean; much quieter acoustically and a submarine could manoeuvre in the deep water there. Submariners are notorious liars about where they are and where they've been but if they tell you they are loath to go anywhere a prang might ensue, I'd (guardedly) believe them. They don't like shallow water. I was about to quote Lance Corporal Jones but thought better!

They could use a surface vessel with a decent SONAR suite to listen for the location device. To cover any area AND listen is almost mutually exclusive. They may need to sprint and drift, otherwise their Own Ships Noise (OSN) may mask what they're listening for.

Otherwise, drop sonobuoys from fixed or rotary-winged aircraft. That might do it. I flew SAR on Air India 182 back in 1985. I was an acoustic specialist on my Nimrod Maritime Reconnaissance crew. We dropped buoys but heard nothing. The water there was over the 1000fathom line and was "quiet". Plus we dropped buoys at each of the 2 datums of wreckage so we were as near to the source as one could be, under the circumstances. We heard nothing. To be fair, sonic location devices then were in their infancy and I've no idea if the Air India 182 aircraft had been fitted out with such a device.

Other commentators here have questioned whether there COULD be wreckage and/or oil/fuel. All I can add is what I saw: In the case of the Air India182, each of the 2 datums (60 nautical miles apart) had an oil slick as a huge "lead-in" feature. At each datum there was a large collection of jumble; all that could float. That's all I'll say on that matter.

I used the word "oil", in all probability for convenience. Some people might nit-pick but such fluids from an aircraft wreck will come from a variety of hydrocarbon, mineral and synthetic sources. On that day, on the surface of the ocean, there was a very obviously "oily" film. The sea was calm. In fact it was a beautiful day and those facts messed with our heads in looking at what we were seeing!

There might be major differences in this particular sad case, today. And so, for what it's worth, I offer these recollections in the hope that they might help!

Dai Farr, your signal to noise ratio is very very high. Thanks for the insights.

Can we please stop talking about submarines being used in the search? A conventional, military size submarine will NOT be operated under the surface in 50-100m of water. It would be akin to trying to stay VFR in a widebody with a cloud ceiling of 2500ft. A typical submarine is at least 20-25m in height from keel to top of conning tower or periscope. Even running at periscope depth would be far too risky due to chance of collision with surface vessels.
Submarine sonar systems are specifically developed to be used when running submerged, surface turbulence renders them useless, so they will only be used as another vessel running on the surface searching if they are even deployed.
Specialist vessels such as hydrographic or exploration vessels with accoustic/sonar/MAD technology will be far more effective.
Having said that, as these systems search on a cone (and will be lucky to be travelling at 6-12 knots), and that the water is so shallow, they will be greatly reduced in their effectiveness to cover a reasonable area.
Given that the water is so shallow, the most effective thing if no visible debris is found would be specialist aircraft such as the Orion if fitted with the MAD booms. They will also cover much more area much more rapidly than any surface search using this technology.

But real world examples seem to tell different stories.
The Space Shuttle Challenger cockpit detached at 45,000 feet continued to 65,000 feet then free fell, slowly spinning for 2 min 25 seconds. Challenger 1

Footage of a go pro falling from 12500 feet, it fluttered and spun at 7 revs per second and took 2 minutes to hit the ground. A Go Pro weights 100 grams. (Note that the footage isn't verified)

Footage of HALO skydivers in free fall from 30000 ft reveal that they free fall for a few minutes before they deploy chutes at 5,000 feet.

Surely the aerodynamics of unknown shapes are impossible to factor?


Mickjoebill

As has been mentioned before here, given the huge number of fishing vessels in those waters every night of any given week, I find it hard to believe that someone (quite a few 'someones' in fact) didn't se or hear something if the aircraft crashed in the immediate area.

I would imagine that part of the SAR effort would be patrol boats going from fishing boat to fishing boat - (and I'm not exaggerating when I say that that could take *** weeks, if not months) - asking if the fishermen saw or heard anything unusual on the night in question.

40s accelerating at 10 ms^-2 is a final velocity of 400 ms^-1. Terminal velocities are typically less than 100 ms^-1.

Having spent a good portion of my life in countries where people live a hand to mouth existence, I have witnessed many times the looting which occurs after a tragedy. It's sad that some people live in conditions where an airplane crash represents the opportunity of a lifetime, but it's true for a large part of the world's population.

From what I've read here, the area is filled with small fishing boats, and my opinion is that no one would report a crash before scavenging whatever debris was left on the surface.

To avoid the requirement for a Chinese visa. If using a stolen passport the traveler is unlikely to want to drop it off at the local Chinese Embassy for 24-48 hours then return to collect it in case they check its legitimacy. As noted earlier if transiting China for up to 72 hrs you don't need a China Visa.

Question is, were these miscreants anything to do with the disappearance of MH370? Or were they just criminals looking to obfuscate anyone trying to track them?

Hell, it could have been a couple of Jason Bourne types...

https://pbs.twimg.com/media/BiUsUpRCQAAS4Sn.jpg

For Reference, example of debris from Swissair111- crashed at full power.

Source: https://twitter.com/search?q=mh370%2...ah&mode=photos

RE HARMONIC VIBRATIONS
 

mseyfang POSTULATED that perhaps some sort of flutter issue may have led to instant disintigration.

Theoretically possible- but not probable.

Flutter testing is standard in the industry, and FBW can automatically reduce such possibilities. helicopters are a different animal.

One known case of disintegration re flutter/harmonics of as fixed wing is the early Lockheed electra- several were lost. After finding out what really happened, the related problem was fixed- and a few dozen/hundred are still flying after 40 50 years - they afre called navy P-3.

The onset was due to a faulty engine mount design which came loose after hard landings. This allowed the turboprop engine- turbine to go into a whirl mode ( via gyroscopic action) at what was the natural frequency of the wing. In a few seconds, the wing ( VERY STIFF ) disintegrated.

That was in the late 50's as I recall.

AS to 777 - not impossible - but IMHO VERY unlikely !!

Simply too much redundancy and a flexible wing.

And NO its NOT like galloping gertie issues...

An environment filled with active fishing boats in relatively shallow (<100m)
water sounds to me like a nightmare environment for any type of sound detection.
Just because the noise clutter from these ship is principally at lower frequencies does not mean the higher frequencies are clear. Rather there is a comprehensive fog of noise that blurs everything.
Imho, they cannot locate anything using the pingers on the ELTs unless they are really close, within a few miles at most, so finding debris visually is an essential prerequisite to knowing where to look. The range could be increased if the authorities can enforce a fishing holiday, but that would be unprecedented afaik.