Malaysian Airlines MH370 contact lost
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There do not appear to be sufficient facts to justify searching the Indian Ocean. It is a desperate action that is motivated in part to placate public opinion... better to be seen doing something rather than nothing.
The possibility of finding the floating wreckage is extremely small unless there is a small defined area of search and even if wreckage is found, locating the site of entry is almost impossible.
It is not what anyone wants to hear but it is closer to reality.
Better to investigate other possibilities and leads rather than waste resources in this way.
The possibility of finding the floating wreckage is extremely small unless there is a small defined area of search and even if wreckage is found, locating the site of entry is almost impossible.
It is not what anyone wants to hear but it is closer to reality.
Better to investigate other possibilities and leads rather than waste resources in this way.
Therefore if the aircraft flew faster then it MUST cover a greater distance (+/- 20 mins worth - see a previous post).
60q of fuel at x, consumed at 15q per hour equals 4 hours' endurance after x.
Same aircraft but with 80q of fuel at x, consumed at 20q per hour still equals 4 hours' endurance after x.
They'll run out of fuel at the same time (A) but won't run out of fuel at the same place (along the arc plus post fuel-exhaustion 'glide').
That's why I guess a change in understanding of FOB at x is changing the estimated impact location.
This talk about redirecting "the search" is fine, but surely there are two very different searches going on here.
The crucial one for the fuselage and blackbox will have found a new focus now, yes.
But the wider searches for floating debris must surely continue on in the same general areas where bits were spotted by Chinese, Thai and Japanese satellites. Perhaps this latter search will have had to become wider though.
The crucial one for the fuselage and blackbox will have found a new focus now, yes.
But the wider searches for floating debris must surely continue on in the same general areas where bits were spotted by Chinese, Thai and Japanese satellites. Perhaps this latter search will have had to become wider though.
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Correct me if I am wrong but we do not know what speed, direction or altitude the aircraft was flying for most of the flight.
The Doppler analysis does not appear to be able to accurately access the speed or direction other than it was coming towards or away from the satellite.
Given this, the plane could be just about anywhere on the arc.
This does not appear to be a sound basis for the current search.
The search area is based on a series of additional assumptions that really have no basis other than conjecture.
The Doppler analysis does not appear to be able to accurately access the speed or direction other than it was coming towards or away from the satellite.
Given this, the plane could be just about anywhere on the arc.
This does not appear to be a sound basis for the current search.
The search area is based on a series of additional assumptions that really have no basis other than conjecture.
Flight planning 101
I can't believe we've needed 50-odd posts to try to explain what was crystal clear in the original ATSB statement - that in the early stages of the flight, the aircraft burned more fuel than had previously been thought. 
Well 51 posts if I include my own, suggesting that the OP simply re-read what the ATSB had said, which the mods clearly thought was unhelpful and deleted, as they no doubt will this one too.
Well 51 posts if I include my own, suggesting that the OP simply re-read what the ATSB had said, which the mods clearly thought was unhelpful and deleted, as they no doubt will this one too.
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Mesoman wrote:
Why use 37kHz when lower frequencies travel longer in water? I'm just curious.
Submarines listen to low audio frequencies, which can travel very long distances underwater.
The pinger is at a much higher audio frequency (37Khz) which is attenuated (reduced in strength as it travels) much more quickly. It might not even be detected from the surface in a deep ocean, much less at distances of many miles.
The pinger is at a much higher audio frequency (37Khz) which is attenuated (reduced in strength as it travels) much more quickly. It might not even be detected from the surface in a deep ocean, much less at distances of many miles.
Why use 37kHz when lower frequencies travel longer in water? I'm just curious.
Think about subwoofers in a stereo system; generally there is more amp power going to fill out the lowest octave than is going collectively to the other nine octaves.
They would have been trading off detection distance against battery life.
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SEARCH UPDATE: 1700HRS local time 29th March (2100GMT 28th March).
One of the Chinese Iluyshin IL-76's has spotted three debris objects today in the current search area, that are coloured, white, red and orange.
These objects were sighted from 300M altitude (1000' approx).
No confirmation of the debris being MH370 wreckage will be available until ships find the debris spotted today. This will not be likely until tomorrow.
The search is still on for the two blue and grey objects sighted from the air yesterday. HMAS Success is not expected in the search zone until tonight.
Weather in the search zone deteriorated in the afternoon with the passage of a weak cold front and associated low cloud.
The weather will improve tomorrow with light clearing showers and light scattered cloud.
The Anzac-class frigate HMAS Toowoomba left port this afternoon with the Seahawk S-70B2 helicopter aboard.
http://en.wikipedia.org/wiki/HMAS_Toowoomba_(FFH_156))
The ADV Ocean Shield leaves the port of Fremantle tomorrow with the towed pinger on board to travel to the current search zone.
Ocean Shield is currently just off Mandurah and will reach Fremantle tonight.
http://www.marinetraffic.com/en/ais/...date:lastknown
One of the Chinese Iluyshin IL-76's has spotted three debris objects today in the current search area, that are coloured, white, red and orange.
These objects were sighted from 300M altitude (1000' approx).
No confirmation of the debris being MH370 wreckage will be available until ships find the debris spotted today. This will not be likely until tomorrow.
The search is still on for the two blue and grey objects sighted from the air yesterday. HMAS Success is not expected in the search zone until tonight.
Weather in the search zone deteriorated in the afternoon with the passage of a weak cold front and associated low cloud.
The weather will improve tomorrow with light clearing showers and light scattered cloud.
The Anzac-class frigate HMAS Toowoomba left port this afternoon with the Seahawk S-70B2 helicopter aboard.
http://en.wikipedia.org/wiki/HMAS_Toowoomba_(FFH_156))
The ADV Ocean Shield leaves the port of Fremantle tomorrow with the towed pinger on board to travel to the current search zone.
Ocean Shield is currently just off Mandurah and will reach Fremantle tonight.
http://www.marinetraffic.com/en/ais/...date:lastknown
Last edited by onetrack; 29th Mar 2014 at 09:29.
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IF this new area is the correct area and IF this was a controlled crash / Landing on the water with the assumption of a smoother surface than the 40's would it be prudent to assume the hull remained relatively intact?
If that is the case would the hull have breached / imploded as it sank below 1000 ft or just cracked with small openings.....
I ask this as small debris devoid of the 24 x 14 sightings that amassed in the past area would seem to point towards a controlled splash down with hull intact.
On a side note with over 800 objects of considerable size and shape being spotted in a low trafficked area of the ocean (initial search area) with practically no habitable land within 1500 km that is a lot of floating garbage and would be worth a treasure hunt someday.
If that is the case would the hull have breached / imploded as it sank below 1000 ft or just cracked with small openings.....
I ask this as small debris devoid of the 24 x 14 sightings that amassed in the past area would seem to point towards a controlled splash down with hull intact.
On a side note with over 800 objects of considerable size and shape being spotted in a low trafficked area of the ocean (initial search area) with practically no habitable land within 1500 km that is a lot of floating garbage and would be worth a treasure hunt someday.
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Searching in Silence?
Has anyone noticed that the information stream on this "search" has dried up?
The latest tweet I have seen is that HMAS Toowoomba (an ANZAC class frigate) has left Garden Island, near Perth for the search area. Transit time about 3 days.
The latest tweet I have seen is that HMAS Toowoomba (an ANZAC class frigate) has left Garden Island, near Perth for the search area. Transit time about 3 days.
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One thing we do not know which may have affected the range of the aircraft is exactly how far WNW it flew from Butterworth. It appeared to drop off primary radar at 200nm. Further elucidation of this may have been possible by data collected by other agencies not disclosed for security reasons.
However, if this is so, it does make it even more confusing that the final position appears to be closer to Perth. It would help to explain the time and speed, however.
However, if this is so, it does make it even more confusing that the final position appears to be closer to Perth. It would help to explain the time and speed, however.
Do a calculation yourself aircraft missing for say 20 days. Initial estimates of drift due currents in the area (say) 2 KPH after dropping buoys and small change in impact point estimate for currents (say) 4 KPH look at the difference in distance. Now say the small change in impact point also put the crash into an area where the vector of the drift current was in a different direction perhaps 070 rather than 140 - again a large change in position.
So a relatively small change in impact point of 100 miles could change drift current and vector of the drift current leading to a large change in debris search area coordinates.
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MM43 - The "information stream" hasn't dried up, the search is ongoing with all available aircraft plus an increased number of ships.
It's just that nothing major has been confirmed, it's still an ongoing "slog". Expect an update from AMSA shortly.
I don't think it will take 3 days for HMAS Toowoomba to travel the approximately 550-600NM to the search zone, she has a good turn of speed, around 27kts maximum. Even at 25kts, that's only 22hrs to travel 550NM.
(EDIT: Toowoomba is currently making 17kts, as her CODOG propulsion system only uses the gas turbine for high speed dashes. And yes, my error, the information I had contained a typo and the distance to the search zone is 1800+km).
It's just that nothing major has been confirmed, it's still an ongoing "slog". Expect an update from AMSA shortly.
I don't think it will take 3 days for HMAS Toowoomba to travel the approximately 550-600NM to the search zone, she has a good turn of speed, around 27kts maximum. Even at 25kts, that's only 22hrs to travel 550NM.
(EDIT: Toowoomba is currently making 17kts, as her CODOG propulsion system only uses the gas turbine for high speed dashes. And yes, my error, the information I had contained a typo and the distance to the search zone is 1800+km).
Last edited by onetrack; 29th Mar 2014 at 11:57. Reason: addendum ..
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onetrack
The problem I have with that statement is that AMSA say it is 1860km to the search area! Whether I believe that or not (their media graphics leave something to be desired), the quoted distance happens to be 1004 NM.
I don't think it will take 3 days for HMAS Toowoomba to travel the approximately 550-600NM to the search zone
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MM43
Yes, this happened which the media obviously thought was of consequence.
"Late on Saturday, a Chinese surveillance plane reported it found three more objects - white, red and orange ............
That was only a few hours ago and hit the papers almost immediately.
I think the time lag between take off and return doesn't help. You get this 9 hour void from 0900 onwards (AEST)
for about 9 hours until the first aircraft returns and the pilot does an interview (if they do).
Yes, this happened which the media obviously thought was of consequence.
"Late on Saturday, a Chinese surveillance plane reported it found three more objects - white, red and orange ............
That was only a few hours ago and hit the papers almost immediately.
I think the time lag between take off and return doesn't help. You get this 9 hour void from 0900 onwards (AEST)
for about 9 hours until the first aircraft returns and the pilot does an interview (if they do).
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It would not be hard to incorporate a transponder, which would only use power when interrogated by a SAR vehicle
Practically it would need quite a bit of power for a decent receiver and signal processor to unambiguously detect the interrogation. Perhaps overall life wouldn't be improved much?
On the other hand, modern MEMS technology may make the detection much less power hungry?
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For what it`s worth.
10 minutes ago ,i talked to one of my clients ,who stays every year in Malaysia from De. til March-
He told me public opinium there is,that the pilot has stronger ties to radical/anarchistic circles than the authorities have told us.
10 minutes ago ,i talked to one of my clients ,who stays every year in Malaysia from De. til March-
He told me public opinium there is,that the pilot has stronger ties to radical/anarchistic circles than the authorities have told us.
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Ian
I think you summarize very nicely.
If it's right.
There shouldn't be a reward for the people (not necessarily the technical team - it could be the Australian cabinet office) who set the zone for the wild goose chase that took place pre-Friday. Just an invoice for all the wear and tear, jet fuel, lost sleep, potential risk to crew and needless gigabytes of satellite imaging.
There should be more than enough information available to get it right.
There are eight precise distances to the satellite with eight reasonably accurate speeds away from the satellite. You're spot on that the substantial motion of the satellite N-S about its station rules out the North, and the ~100km/h satellite speed is a big deal for calculating the resulting Doppler signal - as the Straits Times powerpoint picture shows.
As you say, there are also the practical limits on endurance, plus some ropey radar information from some less than alert countries near the point of origin.
There should be a clear Monte-Carlo distribution of locations where it might have sunk.
I fail to see the reason for all the Australian and Malaysian governments' PR hoopla, trumpeting random pictures of whitecaps from random satellites, and using such "information" to divert searches.
So far, Inmarsat alone have made a contribution to where the search should be carried out. If nefarious agencies do actually have information to help show where it actually came down, based on more powerful assets, but don't want to be seen saying it, then they should just call the Australian MOD and make things happen right.
There are only so many batteries in the recorders' sonar beacons, and that's what's important: finding a few bits and pieces on the surface three weeks after the crash is no use to anyone. We already know that it flew for hours and hours, and probably just ran out of fuel. It's hard to see how finding a piece of fairing or overhead bin on the surface will reveal anything useful about events three weeks ago, other than as a drift marker back to the crash site.
I think you summarize very nicely.
This is a considerable scientific effort which has pulled together multinational specialists in widely diverse areas working at the ragged edge of what is possible in their fields. I hope that their work does not go unrewarded.
There shouldn't be a reward for the people (not necessarily the technical team - it could be the Australian cabinet office) who set the zone for the wild goose chase that took place pre-Friday. Just an invoice for all the wear and tear, jet fuel, lost sleep, potential risk to crew and needless gigabytes of satellite imaging.
There should be more than enough information available to get it right.
There are eight precise distances to the satellite with eight reasonably accurate speeds away from the satellite. You're spot on that the substantial motion of the satellite N-S about its station rules out the North, and the ~100km/h satellite speed is a big deal for calculating the resulting Doppler signal - as the Straits Times powerpoint picture shows.
As you say, there are also the practical limits on endurance, plus some ropey radar information from some less than alert countries near the point of origin.
There should be a clear Monte-Carlo distribution of locations where it might have sunk.
I fail to see the reason for all the Australian and Malaysian governments' PR hoopla, trumpeting random pictures of whitecaps from random satellites, and using such "information" to divert searches.
So far, Inmarsat alone have made a contribution to where the search should be carried out. If nefarious agencies do actually have information to help show where it actually came down, based on more powerful assets, but don't want to be seen saying it, then they should just call the Australian MOD and make things happen right.
There are only so many batteries in the recorders' sonar beacons, and that's what's important: finding a few bits and pieces on the surface three weeks after the crash is no use to anyone. We already know that it flew for hours and hours, and probably just ran out of fuel. It's hard to see how finding a piece of fairing or overhead bin on the surface will reveal anything useful about events three weeks ago, other than as a drift marker back to the crash site.
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What I am saying is that assumptions have been made regarding constant speed, altitude and direction after the last radar contact. Further similar assumptions have been made between the point of loss of transponder contact and last radar contact but with supporting evidence as a result of some sketchy radar data.
The range is calculated using these assumptions and then fed into the known ping data and low resolution Doppler calculations.
If these assumptions do in fact result on the location of wreckage it will be a result of some very clever investigation and math but also a large slice of luck based on someone's hunch.
Given the flight time that is known (subject to the last ping and partial ping uncertainty) The assumption that the aircraft remained in flight until fuel exhaustion is a good one. It is also a likely assumption that the aircraft continued on a constant heading, altitude and speed (assuming no pilot). But constant speed and altitude are reliant on autopilot control.
What that constant speed and altitude may have been is an educated guess. It also assumes without autopilot, the trimmed aircraft could not have remained in flight oscillating between altitudes on an inexact heading.
The range is calculated using these assumptions and then fed into the known ping data and low resolution Doppler calculations.
If these assumptions do in fact result on the location of wreckage it will be a result of some very clever investigation and math but also a large slice of luck based on someone's hunch.
Given the flight time that is known (subject to the last ping and partial ping uncertainty) The assumption that the aircraft remained in flight until fuel exhaustion is a good one. It is also a likely assumption that the aircraft continued on a constant heading, altitude and speed (assuming no pilot). But constant speed and altitude are reliant on autopilot control.
What that constant speed and altitude may have been is an educated guess. It also assumes without autopilot, the trimmed aircraft could not have remained in flight oscillating between altitudes on an inexact heading.
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On the other hand, modern MEMS technology may make the detection much less power hungry?
We (the industry) has to address this issue now and ensure that 'black boxes' are interrogatable for years if not decades. It isn't that hard, it's down to cost and the will.
Of course, that's today's public issue. Tomorrow it'll be the safety of composites, fuel systems, anti-hijack, anti-explosives, etc. and the public will forget about the need to find lost aircraft in savage terrains.
It's hard to see how finding a piece of fairing or overhead bin on the surface will reveal anything useful about events three weeks ago, other than as a drift marker back to the crash site.
