As I’ve discussed in earlier posts, by its own calculations the ATSB has already searched most of the high-probability areas of the Indian Ocean seabed in its quest to find the wreckage of MH370. The only remaining area of relatively high probability that has not been searched is a stretch along the inside the 7th arc.
(In the image above, the area that had been searched prior to the release of the ATSB’s December 3 report is outlined in black.)
Yet this is not where the search is currently underway. According to ship-tracking conducted by Mike Chillit, Fugro Discovery has spent the weeks since the ATSB issued its report searching an area 40 nautical miles beyond the 7th arc, in the pale blue “low probability” area of the ATSB’s heat map.
It’s hard to understand why.
UPDATE 12-22-2015: I was delighted to learn that Richard Cole is back on the case, paralleling Mike Chillit’s work by collecting and collating ship-movement data in order to understand what areas have already been searched. Richard has given me permission to reproduce one of his charts, which shows the situation much more clearly than my amateur effort above. I’ve outlined the area already searched in light blue. One thing I notice looking at this is that the unsearched high-probability area near 87.5 N 37.5 S hasn’t even been bathymetrically scanned yet! Click to enlarge:
My understanding is that they are searching the southern area now because of the seasonal WX conditions and logistics considerations. WX will turn bad in the south first.
@airlandseaman: what are your new best estimates for speed (KGS) and altitude at 00:11:00 (6th Arc), given the Dec. 3 reports? Thanks in advance for any time and energy you have to spare helping recalibrate my stochastic model.
If anyone else has these best estimates, I’d love to see them. Thanks.
Looking at the red area outside the box, makes me wonder about the early “spaghetti course”, which was later explained by heavy weather strategy. Though it was doubling back numerous of times, which would counter indicate, that these ships cannot/do not want to turn but point the bow into the wind and waves.
Does have anyone (Richard Cole maybe?) have coordinates for the early “spaghetti course”? Does that coincide with the new outside the box high priority area?
Correction to previous post:
Found Brock’s post in old thread: JACC 17th Dec 2014 update stated “systems issues” and not weather related as I wrote above.
In the Dec 3 report, ATSB provided new estimates for (1) the AES logon time delay [120 seconds after fuel exhaustion], and (2) the difference in engine flameout times [up to 15 minutes].
The first change moves the time of fuel exhaustion out from what was previously believed to be ~00:15:49 to ~00:17:29. The second change would move the time of the right engine flameout to as early as 00:02:29. The first change seems reasonable, assuming additional AES and APU test data was recorded to fine tune the logon time delay. However, ATSB gave no reason or analysis showing why the right engine ran out of fuel “up to 15 minutes” before the left engine. The FI report on March 8 contained sufficient information to estimate the fuel burns in each engine. (Download Excel sheet here https://goo.gl/zG0B42 and note all tabs containing data from FI.) That data supports a 5 minute difference. Moreover, ATSB stated in private email correspondence that the SWG had also estimated 3-5 minutes. I see no reason to doubt the 5 minute fuel analysis. I believe the “up to 15 minutes” number is intended to provide a very conservative worst case scenario for the limited purposes of the Bayesian statistical analysis. But it is very likely that the actual number is much closer to 5 minutes, thus a right engine flame out time of ~0012:29, 90 seconds after the 6th arc. If that estimate is good to say, ±90 seconds, then MH370 would not have slowed or descended prior to the 6th arc (due to fuel exhaustion).
@Brock
It does not matter. The search area is nowhere close. You should know that based on your own analytics. When you ask I question like this I wonder if you are ass kissing.
@airlandseaman, There is less than a degree of latitude difference between where they are looking and where they should be looking; it’s about 60 nm distance as the crow flies–I don’t think there is a significant difference in the weather patterns.
@Jeff
Thanks for pointing that. I noticed exactly the same thing, but refrained from commenting since my issues with ALSM are well known.
@Jeff You only described your preferred area as inside the 7th arc. I assumed you were referring to the much longer area inside the arc all the way up to S32 degrees. In any event, I think it was FUGRO’s Kennedy has stated they are looking in the south first due to good WX cond there this time of year.
I have been a long time advocate of looking at least 20-30NM inside, based on the simulator tests back in Nov 2014. So I agree that it is important to look there.
@ALSM
No. Actually Jeff was asking why not search the highest probability areas first. A very reasonable question, IMO.
DennisW: Where to look NEXT is a function of many variables, as I have attempted to pint out. The so called highest probability area is only one factor that goes into the calculus. WX and Logistics are two of the others. I am not defending the ATSB choices. I’m only trying to explain that the Bayesian analysis is only one driver in the overall equation.
@Dennis: I’ve been chastised by all sides for being polite. I only get mad when I’m lied to.
What I am trying to resolve is a paradox:
1. the ATSB believes engine 1 flamed out at 00:04 UTC, +/- 2min or so.
2. the ATSB is searching in a place rendered impossible by 1.
I’m pretty sure @airlandseaman agrees this is a paradox: it was the IG who spearheaded the work showing the distance between Arcs 6 and 7 was hard to cover even with a LATE 1st engine flameout; cut this power out several minutes sooner, and it becomes mission impossible. He has chosen to resolve the paradox by saying the ATSB is simply wrong about 1.
This is a common tactic. Back when I pointed out the ATSB’s search at s21 was rendered impossible by the ATSB’s own fuel limit of record, several helpful contributors to this forum explained to me that the ATSB miscalculated its fuel limit.
Let’s think about this concept for a moment:
“Sure, they’re searching in a spot their own data says is impossible, but this is nothing to worry about, because their data is wrong.” This argument has two corollaries:
A. The ATSB must THINK it is searching in a place that is impossible for MH370 to have reached, and
B. The fact that they are actually searching in a feasible location must be just a lucky fluke.
The mind reels.
@airlandseaman: can you please construct for us a sample path – with precise altitudes, latitudes, longitudes, and times – which spirals down in a manner consistent with your flight sim results, is near FL(0) at 00:19 (as a paper you’ve co-authored argues), is descending at 15,000’/min at 00:19 (as you’ve consistently said was likely), and still manages to impact more than 20 nmi inside Arc 7 (as you now apparently deem eminently plausible).
I wish to improve the calibration of my stochastic model. It still considers such paths patently absurd.
Maybe some progress by France. A comment on MH370 France facebook page (translated by Google):
“After 20 months of fighting, finally three French judges went to Malaysia to meet the team that officially investigating the MH370.
Is this the beginning of a real independent investigation ? we have some answers ? I would always hope”
An update on the search at 06:30UT 22nd December.
Discovery has been operating in a concentrated area for several days and is making its 5th scanning pass through it – see map at link below. There is also a context map showing the wider area.
Harmony is 20km away from Discovery and has been stationary for 24 hours. It has been operating in that area for some days now, starting before Discovery’s arrival.
https://www.dropbox.com/s/m6aj9zfwfs5hxim/Search_update_22-12-15.pdf?dl=0
The FI gave instantaneous fuel flow values at takeoff and climb for the two engines. The accuracy of fuel flow transducers is of the order of 1 % and in the light of turbine engine performance characteristics the extrapolation method used by the IG makes no sense at all. The ATSB apparently used “historic fuel burn data”, i.e. the fuel quantities in the tanks before and after flight, a more accurate measure of fuel consumption during flight. See ATSB Report of 3 December 2015, End-of-flight, Engine Flame-outs:
Another interesting detail in the same report is this quote from Figure 6: End of flight sequence:
Since the OEI level-off altitude at Maximum Continuous Thrust (MCT) is greater than 30,000 feet, that altitude indicates that the maximum thrust selected by the Autothrust after the first engine flame-out is less than MCT. That is also evident in ALSM’s simulation where the airplane decelerated at 0.315 kTAS/second, or 0.0165 “g”, equivalent to a steady gradient of descent of 1.65 %.
The following graph compares the simulator data to the OEI FCOM data at MCT: http://i.imgur.com/GT5upLm.jpg
Is there any evidence that both the engines were operating after 18:22?
In an attempt to better understand the sequence of events that would occur during fuel exhaustion, I reached out to a highly experienced airline captain who also runs a training simulator and blogs proficiently about this kind of topic. (He works for a major US carrier and is sensitive about being identified in this particular context.) He walked me through the phases of the endgame:
— According to the ATSB’s fuel analysis, sometime after 00:02:30 the right engine flamed out. As @airlandseaman has pointed out, we don’t really know when this was; based on “Fig 6: End of Flight Performance” published on December 3, the ATSB seems to think this occurred sometime between 00:02:30 and 00:07:30. Prior to that point, in order to have arrived in the vicinity of the current search area, the plane would have had to have been traveling at around 480 knots groundspeed. After the right engine stopped, the autopilot would try to keep the plane at altitude while the autothrust increased the remaining engine’s power setting. “At cruise altitude the thrust limit would be set to either CRZ (Cruise) or CLB (Climb), depending on operator specification. CRZ limit is less thrust than CLB limit. While Boeing typically deliver the aircraft with a default of CRZ, we used to find that in turbulence when cruising at very high altitudes (for weight), particularly in any kind of mountain wave type turbulence, CRZ was not enough and you could find yourself on the back side of the drag curve without the thrust available to recover speed or even maintain altitude. I believe most operators have the pre-select set such that CLB thrust limit is annunciated when the aircraft levels off in cruise. If this is the case with MH, then at that altitude CLB is CON is TOGA – different labels, same actual amount of thrust. CRZ however would be a lower thrust setting, which in this scenario would only mean that the remaining engine would deliver slightly less thrust, airspeed decay in the initial stages would be slightly faster, the aircraft would be established in a slightly steeper one engine descent, and would stabilise at a slightly lower altitude (in the order of a few thousand feed I suspect). If there is any 777 that could have been left at CRZ it would be the 200ER which always had plenty of thrust. but if MH have 200’s or 300’s they’ll have a common setting across all 777’s and it will be CLB.”
— The aircraft would maintain altitude, bleeding off speed, until its wings were no longer generating enough lift to maintain altitude. Then it would start to sink. “In the single engine loss scenario, the aircraft would not stall. It would slow to stick shaker – which is pre-stall warning – then at some point before the aerodynamic stall (which in the 777 includes aerodynamic buffet as the airflow breaking up over the wing washes back over the tailplane) – the autopilot pitches the nose down. This initial pitch down causes the aircraft to accelerate away from the stall and away from the stick shaker. However at this point the AP is in a knd of a no mans land. The annunciated mode is failed-VNAV, the autothrottle is in SPD. It’s not in an established normal mode, it’s in kind of a care taker pitch based descent mode. It is not unusual for the aircraft to re-encounter the stick shaker again during this descent, then have the AP push the nose down again, etc. Until it gets to the point where sufficient thrust exists from the remaining engine that the AP does not need to continue the descent to maintain a safe speed. I honestly have no idea what would happen after that. It could even eventually start climbing again as it burns off fuel. It depends on the mechanics of the AFDS failed VNAV mode, which only Boeing would know.”
— A 777-200ER weighing 174,000 kg can fly at 29,000 feet on one engine. But a plane that is behind the power curve will not be able to maintain this altitude. “That altitude would be relevant for best one engine cruise speed, and with the AP focussed on height maintenance rather than stall protection. With the airspeed much slower than best lift drag, I suspect the actual stabilisation altitude might be lower. When cruising one engine (or all engine for that matter) your best and maximum altitudes are highly speed dependant. Fly very slow of very fast and these altitude are lowered. CRZ thrust limit would also lower the maximum altitude.” However, given that the ATSB seems to think that the plane could have stabilized at 29,000 feet, I think it’s more than possible that the plane descended at faster than stick-shaker speed and wound up stabilized at 29,000 feet at around 390 knots true airspeed. Given @alsm’s previously published figure of -0.3 knots/second deceleration post first-engine flameout, this state of equilibrium should have been reached within about five minutes, or no later than 00:12:30. It should be noted that if MH370 decelerated to 390 knots soon after the 6th arc it is very hard to understand how it could have reached the 7th arc.
— The ATSB attaches a much higher confidence level to the timing of the left-engine flameout, placing it at 00:17:30. At this point the aircraft is “trimmed for a cruise airspeed vertically, trimmed for a cruise setting laterally, (but that usually means almost no rudder trim) now in an idle thrust low speed descent.” I interpret this to mean that the nose will drop and the plane will accelerate to an indicated airspeed of perhaps 280 KIAS. However, given that only 90 seconds remain before the 7th ping, it’s nearly impossible to understand how MH370 could have reached the ping arc.
As I see it, there are two possibilities: either the ATSB’s understanding of aircraft performance is incorrect (as Mike suggests) or the ATSB’s understanding of aircraft performance is correct and events did not unfold as described over the SIO search area (as Brock suggests).
Personally, it seems to me that the experts assisting the ATSB should be able to model quite accurately the anticipated behavior of the 777, so I lean toward the latter view.
@Brock
You are for sure a breath of fresh air. Please ignore my frustration which bubbles to the surface from time to time.
Likewise ALSM. Your sincerity and analytical skills have never been in doubt, and I certainly appreciate them.
Discussions around the details of the end of flight bring out the worst in me. Since I am so convinced the current search area is far removed from reality. As convinced as you are, Mike, that it is generally correct, and only needs refinement.
Having said that, I need to step aside until the aircraft is found there (which I certainly hope it is), or until the search strategy is reset. Sniping is counter-productive, and I apologize for it.
@jeffwise:
In your last post, when you write “I” or “me”, is it you or the captain speaking?
I agree with the first bullet, but after that it seems to be mostly guessing, and I don’t fully agree with those guesses. Apart from the timing of events, a lot depends on the initial speed and altitude. In the simulator test that ALSM has made available, the airplane was initially at FL350 and M.8, 461 kTAS. After the first engine failure the airplane decelerated at constant altitude to 360 kTAS in 5 minutes 25 seconds, i.e. 0.31 kTAS/second. At that point the second engine failed, the airplane descended while the speed stabilized around 200 kIAS, slightly below the FCOM Flap Maneuver speed of 206 kIAS, the speed at which the airplane was apparently trimmed when the A/P & A/T disconnected. My guess is that the airplane would have maintained that speed if it had not banked to extreme attitudes due to the applied out-of-trim.
@Gysbreght, When inside quotes, “I” refers to the captain, otherwise to me. Yes, there is much guessing, but I don’t see a great deal of difference between what you propose and what I described.
@AM2, I understand that the judges have completed their trip to Malaysia. Hopefully one day we may find out what they learned, if anything.
“However at this point the AP is in a knd of a no mans land. The annunciated mode is failed-VNAV”
That sounds like rubbish to me. Is there an annunciated mode “failed-VNAV” ? On the Flight Mode Annunciator (FMA)?
@Jeff:
Regarding your report from the “…highly experienced airline captain…”, thanks for that. I can’t confirm every detail you reported, but everything I learned from the simulator and several SR 777 Captains is consistent with what you reported.
Regarding the descent profile…the timing is important. Assuming MH370 was at typical cruise altitude and airspeed, if the left engine flamed out ~5 minutes after the right, like ATSB first reported, and as my fuel analysis confirmed (based on MH370 indecent flight actual fuel weights and burn rates reported by ACARS), then MH370 would have remained at cruise altitude, slowing down to maintain altitude until the left engine flamed out. OTOH, if the time difference was 15 minutes, then MH370 probably did start descending a few minutes before the left engine flamed out.
Critics that assert that the fuel analysis is flawed need to show why it is flawed and not just dismiss the ACARS data and analysis, or claim the sensors are not accurate with no proof. What we have is imperfect, but it is the best we have. At the very least we know from that analysis that the ratio of fuel consumption (R/L) was 1.018 at TO and 1.013 during cruise/climb. We also know the fuel mass in each tank before TO. Even if the R/L burn ratio did not decrease further during the high altitude cruise phase of the flight, as the trend suggests, there is no way the time difference could be as much as 15 minutes. A 15 minute difference would require a R/L ratio >1.031. There is no way the cruise ratio was more than double the cruise/climb ratio of 1.013. BTW…Richard Godfrey did an independent fuel analysis and came up with substantially the same results I did. And ATSB confirmed back in March that Boeing came up with the same estimate ( 3-5 minutes).
@airlandseaman:
“Critics that assert that the fuel analysis is flawed need to show why it is flawed and not just dismiss the ACARS data and analysis, or claim the sensors are not accurate with no proof. What we have is imperfect, but it is the best we have.”
As I am that unnamed critic, I feel entitled to reply. What I am asserting is that the ATSB has better data than you have, because they know how much fuel was consumed by each engine on previous flights. It is standard procedure to look at the fuel consumed quantities if there is a discrepancy between the fuel flow indications.
“At the very least we know from that analysis that the ratio of fuel consumption (R/L) was 1.018 at TO and 1.013 during cruise/climb.”
You don’t really know that. You only know that the L/R fuel flow indications were different. Do you have fuel flow transmitter specifications that guarantee a higher accuracy than 1 % after x years of service ?
“… there is no way the time difference could be as much as 15 minutes.”
How do you know that?
“A 15 minute difference would require a R/L ratio >1.031. There is no way the cruise ratio was more than double the cruise/climb ratio of 1.013.”
Why is it impossible that the fuel consumption of two 12-year old engines differs by 3%?
“BTW…Richard Godfrey did an independent fuel analysis and came up with substantially the same results I did.”
Well, obviously, since he used the same information as you did.
“And ATSB confirmed back in March that Boeing came up with the same estimate ( 3-5 minutes).”
Reference?
ATTN Brock McEwen, M.Sc.
Independent Investigator
RE: Bayesian Method Request
Dear Mr McEwen,
As you have demonstrated
global leadership in a
scientific format that is
of a purely objective and
unbias nature, please give
consideration to using your
math skills to calculate an
answer to the following 1
question re MH370 et Al
Inmarsat 7th Arc.
Bearing in mind the
following 4 irrefutable
scientific facts;
1) The global Iridium
Satellite network receives
broadcast transmissions
starting at the frequency
range of 1616.0 MHz and
ending at the frequency
range of 1626.5 MHz
2) The Honeywell AMT-3800
Inmarsat High Gain SATCOM
Antenna as used upon MH370
transmits bundles of data
starting at the frequency
range of 1626.5 MHz and
ending at the frequency
range of 1660.5 MHz
3) The global Iridium Satellite
network and the Inmarsat network
mutually collect and receive
broadcast data broadcast on
the 1626.5 MHz frequency by
way of abutment overlap.
4) Iridium had no less then
two if not three satellites in
orbit with a direct line
of sight to receive any and
or all data broadcast at the
frequency of 1626.5 MHz at
and during the exact same
time(s) Inmarsat claims to
have received data as
broadcast from MH370
My one question is this;
What is the probability
factor that the Iridium
Satellite network would
NOT have received any of
the individual bits and or
bundles of MH370 data as
claimed to be received
only by Inmarsat ?
Please note that you might
now become the 1st person to
put forth measurable and
scientific data that debunks
the claims of Inmarsat and
the IG as being nothing
but Junk Science.
And or lest we forget the
fabricated testimony of
Nayira…. you might be the
1st one to scientifically
prove the claims of Inmarsat
and the IG are just another
criminal fraud.
Hope you have a wonderful
Christmas.
Regards,
Andre Milne
Unicorn Aerospace
Military Technology Development
unicornaerospace.com
@aeromilitarytec
c.c.
Marnie O’Neill
Inmarsat
Iridium
IG
@Andre Milne: I would suggest that you lay off the egg nog, but you have been spouting such silliness since well before the holiday season. Your claim of criminal fraud on the part of the IG is baseless. Luckily, no serious researcher takes you seriously.
@Gysbreght,
I tend to agree with your comments regarding the ACARS fuel flow parameters. Even new engines can have a degree mismatch within a defined degree of tolerance. All the parameters (even fuel quantity) have a degree of tolerance.
Looking at the overall ACARS data, the engines are reasonably close; right is vibrating a bit, but left is taking more of the ECS load whilst right is taking more of the electrics.
To some extent the real test is what is left at the end of the flight against where it started. We don’t have the previous sectors but I find the discrepancy between the fuel at uplift interesting.
The APU ACARS report tells us that the APU ran for 4 hours, this could in effect be anywhere up to almost 5 hours. This is the total APU time from arrival to this departure. Therefore somewhere between 240 to 300 kgs of fuel was consumed during the stopover (based on ATSB consumption figures).
Fuel at uplift was L=3700 and R=4500. Left supplies the APU, so lets add 300(max, could have been less) to left to get arrival fuel. L=4000 R=4500; 500kg in favour of right is pretty large for our right guzzling engine?
OZ
Andre Milne:
You clearly have no understanding whatsoever how mobile satellite communications systems work, or how the L band spectrum is shared among multiple systems. Not one of your “…4 irrefutable
scientific facts…” is true. Not even close. It is all garbage. Your statement accusing the IG of “…another criminal fraud….” is both 100% false and libelous.
@Andre: thanks for your kind words. Sadly, I must decline your math problem – my plate is already over-filled with analytical challenges which are, in my imperfect view, a) much more clearly specified, and b) much more likely to help dig out the truth on MH370.
A word of advice: while the IG and I continue to butt heads on a regular basis – and I do grow impatient with the seemingly infinite amount slack many of its members grant MH370 search leadership – I have no reason to doubt that we are ALL just seeking the truth. We should never assume that, just because someone disagrees with us, they must have an agenda.
@airlandseaman and all
kindly please, this my question was probably unanswered before, but is somehow(?) possible to consume at least slightly less fuel by cycling sequence of slow climbs with engines on and gliding with engines off?? or its nonsense near to perpetum mobile? For me it seems not safe and not comfortable, but how much is one able to save this way, if at all?? thanks
1626.5 MHz is the boundary (in frequency space) between allocations to Iridium and to Inmarsat. On the Inmarsat side, it is assigned to Maritime Service, and specifically for communications from ship to satellite.
“What is the probability factor that the Iridium Satellite network would NOT have received any of the individual bits and or bundles of MH370 data as claimed to be received only by Inmarsat ?”
Ignoring the fact that the HGA antenna would have been steered towards 3-F1, not an Iridium satellite, and the fact that no one has claimed that MH370 data were received ONLY by Inmarsat, I will hazard a guess that the probability that the Iridium Satellite network did NOT receive any MH370 data on 1626.5 MHz is 100%. MH370 was broadcasting in the aeronautical service bands, not abutting Iridium’s frequency space and which Iridium would be filtering out.
OZ refers to “… our right guzzling engine”. How much does it guzzle?
From Factual Information, p. 28, “1.6.3.7 Deferred Defects (MR2)” that were outstanding at the time of the flight:
“From Daily Engineering Operations Report (DEOR) – Right engine consumes average 1.5T more fuel per/hour compared to left engine”
Ouch! If I’ve done my arithmetic correctly, the normal fuel burn rate for a flight like MH370 is usually 3-4 tons per hour. Quite an appetite! Something is not quite right.
Brock – I’d be extremely confident in saying that no debris reached the WA coast. While this seems to mean nothing to the gurus of the IG(most of them), it ‘is’ an issue if they are also adamant that it spiraled in. I I don’t think everyone has been entirely reasonable about this part. Plenty of people still defending their castles and I can understand their affinity with the data if you happened to be a leading satellite engineer, but I think we have a problem.
I always felt that if it didn’t turn up pretty quickly then the chances of finding it at all would be crashing. Empty search area, nothing on the WA coast, question marks with the flaperon, and weird politics. I have taken some potshots along the way at people who have given their heart and soul to finding it – but totally out of frustration. We must be getting close to turning a page but it won’t be unanimous – not until those depths have given up everything they know – whenever that is.
And I forgot to mention the absence of acoustic detection. The Curtin mob have been careful to say that this by itself is not exclusive of an impact but this is the only safe thing to say under the circumstances, and there would have been no surprises at all if there had of been a detection. There are some submariners out there who say there should have been something, from somewhere. A few hundred tonnes hitting the water at M1 – that’s a lot of energy and I have appealed to the mathematically inclined to calculate roughly how much but no one wanted to? The planets needed to line up to have a successful search. Instead they are lining up to have us questioning the search.
Matty,
The issue regarding Curtin Univ is one of the weirdest and most intriguing in this saga. Why do they refuse publishing details of their study? Why did they retract their initial statement? Why does ATSB refuse to take it seriously? Or they know where the aircraft is resting but have to spend their budget first?
The issue is that what Curtin recorded was the likely impact on the seabed rather then the sound of the splash. A significant fraction of the kinetic energy during a surface impact goes to the disturbance of the surface (in simple words waves). A fraction goes to the kinetic energy of water, which quickly dissipates. A part goes to the energy of sound.
In case of the seabed impact, the first component is virtually absent. Entrained water results in approximately 10x mass hitting the bed. Acoustic wave can travel in the bedrock with a comparatively small dissipation. As a result, if the surface impact was not at M1 as Mike predicts, it is very likely the sound was originated by the seabed impact.
I had contacted Dr. Duncan with regard to these issues. He (as well as some other acoustic specialists I had chats with) agreed on this. But unfortunately Dr Duncan only repeated official ATSB position: the time is inconsistent with the 7th arc. I had responded that on contrary, the time is very consistent, but have not got any feedback from him since then.
Somehow they are using prior distribution map in their search, not posterior one (based on the fact that flaperon was discovered and no other debris yet)
Oleksandr – Dr Duncan took a lot of care to not set himself up against the ATSB or the conventional wisdom regarding the data. Watching him it looked clear to me he understood that one miscalculated comment would set the dogs in the press running. Curtin were happy to get exposure, but not controversy. He spoke of the data as if it was a law of motion, and that was intentional I believe.
@Oleksandr, @Matty
Maybe I missed something re: acoustic detection by Curtin Uni?
There was the event they recorded at a location West of the Maldives at approx the correct time (00:19?) but I don’t remember any event they recorded from the current search area. I did ask at one stage about their recorders at Dampier but gather they hadn’t been retrieved. Could you give us a quick summary of what you are referring to in your 6:04 post please. “I had responded that on contrary, the time is very consistent, but have not got any feedback from him since then.”
Oleksandr – when a torpedo exploded in the tube of the Russian sub Kursk, subs a long way off heard it. Then the rest went off and obviously everyone heard that as well – admittedly at a deeper depth. My thinking is that an M1 impact should have registered somewhere, remembering that there are now very few places whale researchers can now go to study them without background noise. The fact that they were studiously going over their recordings at all points to the plausibility of a detection, and for a period they believed they had something, but alas – the data. Even with the Mk1 eardrum when underwater you hear that tennis ball hit the surface anywhere near. It should have registered somewhere, with someone.
The engines and propeller shafts of large ships travel well, and in this case we need to turn a few hundred tonnes of 777 into “confetti” in a split second by dashing it into the sea at high speed. That’s a hell of a ruckus being transmitted into the water. I’m thinking in terms of material destruction as much as kinetic energy.
Matty,
If the surface impact was not at M1, but say M0.32, released energy would be 10x times smaller.
There were potential “candidates” for splash sound, however, as advocated by Bobby for example.
But if the aircraft was relatively slow at the moment when it hit the water surface, the sound would be consistent with the subsequent seabed impact, while the absence of surface debris would me consistent with a relatively intact body of the aircraft. Do remember that the whole mass of the aircraft filled with water is ~10 times more than the mass of the “dry” MH370 (with passengers and cargo).
Now recall what sound produces gravel at a beach…
P.S. Torpedo is a different thing. It was not sound of impact, but rather sound of the blast.
AM2,
There were 2 original plots from the sensors at RCS and HA01 stations presented by Curtin University. In addition, HA01 appears to have directional capabilities, but I was unable to find more details.
The delay in signal arrival allowed for calculating the curve of possible source locations, what was presented in ATSB June 2014 report.
I was wondering where this curve intersects with the 7th arc: you may see the location in Fig.5 of my TN on CTS model (dropbox.com/s/8vrt72o783262he/TN-CTS-Rev1.1.pdf?dl=0) or earlier revisions. It appears to be around 101E.
A mystery source near Maldives poped up later, as Curtin University claimed they identified one more station, which recorded the signal. However, neither comprehensive description of this 3rd station nor recorded signal was ever published with sufficient detail. I made several attempts/requests to figure out these details, but I didn’t succeed. How was it concluded that the location was near Maldives?
Even if there were 3 stations, there should be 2 solutions. The two stations allows to draw a line (more exactly a curve). This line crosses a circle defined by the 3rd station at 2 locations, unless it is tangential. If one point is near Maldives, then where is the second point?
I am asking these questions for nearly a year, but still no answers.
@jeffwise …& all the fantastic & interesting contributors…
A Merry Christmas & Happy New Year!!!
I am no expert on sounds waves in water. However, one can still do some simple calculations. (Someone should still check my arithmetic.)
The Kursk disaster generated two blasts – the first of order 0.2 MT TNT equivalent, the second of order 4 MT. One MT is roughly 4.e12 joules. A 200 ton airliner traveling at 300 knots has a kinetic energy of roughly 2.e9 joules. An underwater blast will couple energy to the water more efficiently than a blast (or impact) on the surface. In round numbers, the Kursk blasts were a thousand times more powerful than the impact of MH370. Thus, one should not rely on them to guide one’s expectations.
@CliffG, Merry Christmas to you as well! And to all the readers here–thanks for all your invaluable contributions in 2015, and I hope we all have a wonderful 2016. I think this might be the year…
@Oleksandr
This was all discussed in detail here way back. I can’t remember where this link came from (probably Brock) but here is the paper by Dr Duncan et al..
https://drive.google.com/file/d/0B-r3yuaF2p72X0lqWWQtZEtFRTQ/view?pref=2&pli=1
Using data from a third recorder at Scott Reef it was calculated that the acoustic event was “near the geologically active Carlsberg Ridge southwest of India”. Also see short article in Nature Newsblog 5 Sep 2014. Hope this helps.
Oleksandr/Sk999 – The initial Kursk blast(solitary torpedo) did not register as a vague audio signal. It was more like a – what the hell was that. It was obvious that something very big had happened. No need to filter everything out, it was a monolithic spike.
Oleksandr – your’e making sense alright, but what about the data?? – and yes I did actually say that. I’m going off the data as espoused by many of the hardheads. What happened to the high speed flutter? 300kts into the water – does that mean someone is awake in the cockpit? And does it still produce debris?
ps: I think if it’s down there it almost has to be largely intact, but that doesn’t sit well with official BFO analysis?
Is it a simple case of MH370 splashing down? It didn’t just hit the water – it destroyed itself in an instant. If I drop a plastic up from ten feet it makes a lot less noise than a glass one because it’s destroyed? Even if you subtracted the fuel loads involved, the impacts on the WTC were shocking.
Anyway, I’m off to the beach – Merry Christmas to all!!