Here are some numbers for GE powered B777-200LR Long Range Cruise......

http://i2.photobucket.com/albums/y17...C.jpg~original

http://i2.photobucket.com/albums/y17...1.jpg~original

http://i2.photobucket.com/albums/y17...2.jpg~original

777's don't have a trim ( tail ) tank

Regarding the search, what height of wave brings about whitecaps, foam, and heavy spray? What height of wave then brings about the breakers that one sees in the video that was posted from the Telegraph? Does merely a confused sea cause a lot of foam or does there need to be a good blow over the water as well.

What I am trying to understand is how calm the sea and wind needs to be for even decent SAR spotting? I know they deploy in pretty foul weather, but I can imagine that a lot of white on the water makes the challenge a difficult one at best.

Inmarsat
 

No. At an earth station the incoming RF effectively filtered and downconverted to extract a section of the RF they care about. This downconvered segment is called an IF, and will be a much much smaller chunk of bandwidth.

So the sampling is done on earth, and it is done over a subset of the spectrum.

Thanks Nitpicker and Lost in Saigon,
I stand corrected. Gosh I hope they find this thing.

Another unsettling factor here, is that a leading marine geologist, Robin Beaman, from James Cook University. has pointed out that the seafloor in the aircraft search area is largely unmapped - and there's a chain of undersea volcanoes in the region, the Southeast Indian Ridge.

He's pointing out that the "complex terrain" of the Ridge will make underwater recovery difficult at best - and the lack of 3D sea floor mapping will only exacerbate the problem.

Australia's only sea-floor mapping vessel, the RV Southern Surveyor, was retired in December, and its replacement is still undergoing sea trials.
To say the timing of the aircraft loss was unfortunate as regards our sea-floor mapping ability is an understatement, to say the least.

flt001
 

Ref post: http://www.pprune.org/8401233-post8158.html

Complete fake...

https://www.youtube.com/watch?v=Aow2ErSP3dQ

This video was taken Jan, 2013 and probably in the North Atlantic where this LPG carrier normally makes short runs.

It's a small boat, relatively speaking, and hard to fathom exactly where it would be delivering LPG deep in the south Indian Ocean.

Uncle Fred
Beaufort wind force 6 will cause white caps to form and make it virtually impossible to spot smaller objects in the water.

Try google for images of the various sea states on the Beaufort scale.

Military Interference
 

Like millions of others I'm watching this saga with intense interest. I just flew as pax 6 sectors with AirAsia through Malaysian airspace. I'm a former Captain rank ATC (in an Air Defence environment too) and civilian ATC and pilot. I'm going to throw this in there.
Not much talk of military interference causing the loss of this aircraft. Just say there was a SNAFU (or deliberate) downing. Just say. The country involved steams its ships to the crash site and collects all the debris and bodies.
The Malaysian Air Defence RADAR is spoofed by Mil ECM. Unless you have a very experienced operator, complex spoofing is very hard to detect. How 'hardened' against this type of attack is the Malaysian system? We don't know.

Equally, we have no idea how 'hardened' the Inmarsat system is against a similar spoofing attack.

All have to agree that this is whole event is just bizarre.

There are NO SATELLITE IMAGES ANYWHERE that show a B777 IN FLIGHT along a pathway to the southern Indian ocean? Are you kidding me? None?

Please don't go into attack mode - just throwing it in there... Nothing I've seen so far makes much sense...

Cheers

I was referring to your FL450 comment.
I earlier posted data regarding the difference between real Altitude and Indicated pressure Altitude being up to 2,500' different.

I think there are most probably satellite photos of it, just not photos that any military organization (maybe US NRO?) who has them is going to release to the public.

@Uncle Fred

For what it's worth, here is info on swell/wave size, wind speed, white caps etc
windwater.html

However, some white caps are not real problem in the southern Indian and southern seas generally. This article - Malaysia Airlines MH370: Rescue expert Aaron Halstead describes challenges of southern Indian Ocean search for possible debris - ABC News (Australian Broadcasting Corporation) - gives a good account of the problem in relation to swell height, visibility and depth perception from the SAR point of view (aerial and from ship height).

Uncle Fred, others have posted the various tables of Beaufort wind scales, sea state, etc. All I can add is an experienced searcher's perspective. Firstly, I think the video posted very recently gives a dramatic example of how difficult any sort of search can be under these conditions. In my opinion, the useful search range from the bridge of that vessel is going to be a couple of hundred yards, MAXIMUM!

Strong winds whip up the sea. Gradually, waves develop. Over a period of time a wind covering hundreds of miles causes the ocean to develop a swell. Wave-like, these swells can have enormous wavelengths and in open oceans 150m to 700m may not be uncommon. Local winds can produce waves on top of an established swell. If the wind is from a different direction to the swell, the surface will be even more disturbed. These local waves, depending on their wavelength compared with the wavelength of the swell they ride upon, may break and produce local white water. Anything that produces waves and/or swell will periodically mask anything afloat. Anything that produces white water will also detract from an observer's ability to see a solid object afloat or riding in neutral buoyancy at some depth under the surface.

Continued strong winds will, at a given rate, "rip" the tops of the waves and blow the spume downwind. In sea state 8 or more, all you can sea are lines of spume set in the direction of the wind. And a very difficult spotting environment this is.

To overcome the masking of something afloat by the presence of the waves and the swell, you need elevation. Too much elevation risks missing anything small!!

To the high swells from the Southern Ocean (lets face it, the area under consideration is on the borderline Indian/Southern Ocean) and the waves from recent strong winds in the search area, you must add the spume and local breakers to the factors that diminish an observer's ability to recognise a person or an object in the water.

A RADAR search of the surface may not be put off by the muddled visual spectrum of white and blue water. But swell and wave height will mask RADAR returns and even return unwanted ones called "clutter". And given that what may or may not be on the surface is almost certainly not going to be generously RADAR-reflective, that's not an enormous help either.

I have only experienced Nimrods as a search platform. At 200 feet, if you mentally extended the 4A tanks forward, you were looking at about 3 nautical miles from the aircraft. A similar exercise with the wingtips or Loral pods, 5nm. Looking for something the size of a person even out to 3nm is not easy, and even if they are wearing a dayglo vest. 5nm? Forget it!

This is an enormously difficult task in an enormously difficult and unfriendly part of the world.

Dai - ineteresting post.
I thought military radar would be able to see through the waves to a certain degree - obviously wrong there!
Wouldn't something semi metaliic stand out very strongly on radar, even in a horrible State 8 sea?

Good information. Thank you. Lends a bit of perspective as to what one sees below from FL 350...

If the aircraft did any compensating, it could compensate more or less to zero, since it has GPS. From the charts, it does not look like there's any compensating happening on the side of the aircraft. That's why Doppler shift jumps when it turns.

Anyhow, this is the best I could do to "reconstruct" their "reconstruction" of the south track. Scales are different, I have no idea why. Even the zero in the original chart is not a zero. (The "knee" around 20:00 UTC corresponds to the Doppler shift going through zero and changing sign as the aircraft passes the closest approach to the satellite, somewhere near the equator.) But at least qualitatively there's an agreement: http://i61.tinypic.com/abo2n7.png This corresponds to the aircraft going off at heading 185 at 450 kts from 18:30 UTC and beyond.

I can't quite tell how they came up with whatever north route they used. There seems to be no way to draw a route that agrees with their "predicted north track" and ends up at 40 degree arc. Here's one way to look at it: their "predicted north track" has no apparent sign changes after 18:30 (we can assume that their "100 Hz" is near real zero, and the red line on the official plot does not get near 100 Hz.). Therefore, the aircraft flying along their "north track" has large consistent Doppler shifts all the way. But they began at the ~32 deg. arc at 18:30 and got only to 40 deg. by 0:11.

I can draw an approximate mirror image of the south route and get good agreement with "measured data" if I send it over Bangladesh and Nepal into south Kazakhstan.

About the only real conclusion that can be drawn here is that there was nothing remarkable happening to the aircraft after 18:30. It was not zigzagging or making any sharp turns. If it went south, I get an OK agreement simply assuming a constant 185 deg. heading (even without corrections for magnetic declination a la Cpt Kremlin above). This is not the track of an aircraft that tries to avoid detection.

Dai Farr
 

It's a fake video. Taken in Jan, 2013, most likely in the North Atlantic.

Always makes sense to confirm sources before commenting upon them.

https://www.youtube.com/watch?v=Aow2ErSP3dQ

Interesting, hamster3null. One question - how does it look at lower or higher speeds? Do you get the same profile but just at a different heading? Or does the plot actually differ?

(As I understand it, and I may be wrong or missing something, they don't know the actual speed of the aircraft, or even that that speed was constant over the 7 hrs. Rather, they only know the difference in relative velocities at points in time. As a result, while the velocity and position for the satellite are known, one has to posit assumed heading/assumed speed pairs for the aircraft, each of which give the same difference in relative velocity, but correspond to a different track in real life.)

Unfortunately, radio waves are too attenuated by the medium of water to allow useful penetration from a RADAR detection point of view.

Semi metallic? I'm afraid it's the 64,000 dollar question. There are too many variables to come up with an answer anyone would feel comfortable with.

When we were out hunting Red October and its ilk, we had all manner of detection ranges given to us from a variety of sources. But the best way to catch the b****r was to literally test the water. We would drop in a bathythermal buoy. As the thermistor head descended it gave us a trace of the thermal profile of the water, locally. From this, once we had consumed our dairy cream sponges, we could establish a sound velocity profile.

If you want an accurate idea of the sort of track spacing to employ in "this" body of water, you would ideally lob something of comparable RADAR reflectivity and/or visual reflectivity into the water and do a RADAR and visual search for it. Of course, most maritime patrol aircraft don't carry conveniently-sized (for the launchers) objects in a variety of materials to experiment with in this way. Flotation devices on sonobuoys are not in dayglo colours.

One of our crew members had experimented with modifying a sonobuoy with a RADAR reflector. His idea had been that if he could convince the manufacturers to incorporate such a thing, then Nimrod Dry sensor operators (the above-water team) could draw some benefit from them (i.e. practicing RADAR homings) as well as we Wet sensor operators (the acoustics team) could derive from the data they were primarily designed to yield. Unfortunately, he was collared by the harbourmaster and almost sparked a live Search and Rescue incident when, in response to, "What the b****y hell are you doing?" he declared there was a buoy in the water! (NOTE: The phonetic impact of this ONLY works with the British pronunciation of "buoy".)

Track spacing in any search is one of those "what do you think" decisions. Might a droppable device, based on a sonobuoy, with a dayglo flotation device (as opposed to military green) help lookouts establish a realistic detection range? If the RADAR could pick it up, then you have a measured visual range, as opposed to a "guestimate". Calm seas are one thing. But in this case, the searchers are on a hiding to nothing. A measured visual range established like this also gives the rest of the world (including Prime Ministers, Presidents) an honest idea of what they are truly up against. Cost of such a device (plus delivery of course). Still peanuts by comparison with the overall operational cost!!

nitpicker330

Anything above FL400 doesn't seem possible with their payload weight. If the airplane had an initial cruising altitude of 370-390 then it could get above 410