Go Back  PPRuNe Forums > Flight Deck Forums > Rumours & News
Reload this Page >

Malaysian Airlines MH370 contact lost

Rumours & News Reporting Points that may affect our jobs or lives as professional pilots. Also, items that may be of interest to professional pilots.

Malaysian Airlines MH370 contact lost

Old 10th Aug 2014, 22:11
  #11461 (permalink)  
 
Join Date: Jun 2009
Location: Canada
Posts: 451
The ATSB won't just pick search areas at random. Any area they pick will be based on advice from the groups studying satellite communications data and aircraft performance.
MG23 is offline  
Old 10th Aug 2014, 22:17
  #11462 (permalink)  
 
Join Date: Apr 2009
Location: Oakland, CA
Age: 68
Posts: 427
We are thus left with only unlikely - possibly highly unlikely - potential explanations.
There is a difference between human behavior and what is likely and/or unlikely and purely technical things. Human behavior as we know from history of aviation can be so aberrant that anything however unlikely can't be discounted but on the other hand purely technical aspects - here what is likely and unlikely remains pretty much constant and I don't think this particular accident will surprise us a lot in technical aspects (if we ever solve it in its entirety) but human behavior can astonish us again.
olasek is offline  
Old 11th Aug 2014, 00:41
  #11463 (permalink)  
 
Join Date: Nov 2004
Location: Perth - Western Australia
Age: 71
Posts: 1,806
I've just spent 3 weeks on Cocos-Keeling Islands and I was stunned at the absolutely vast amounts of flotsam and jetsam littering the shores of the islands.

I was always under the impression (now sadly corrected) that the Indian Ocean was one of the worlds cleanest oceans, and I was very pleased to live on the Eastern edge of it, and revel in its cleanliness.
The truth is, the Indian Ocean is a watery garbage pit, on a par with every other world ocean.

Much of the flotsam and jetsam has Asian origins, and much of it is reputed to be remnants of the Aceh and Fukushima tsunamis.
I believe a lot of it is even more recent and is a result of purely a lazy disposal attitude, on a large percentage of the population of the above nations.

Surviving MH370 wreckage (and there is bound to be some) would be buried in the overwhelming volume of general rubbish that populates the Indian Ocean.

AFAIC, the greatest failure on the authorities part is not immediately issuing a reward notice to the populace of every nation and every island and continent bordering the Indian Ocean, for a monetary reward for any possible aviation-related flotsam or jetsam found in these areas.

Even just one small wreckage item from MH370 would add to the tiny levels of available information and enable researchers to try and calculate the track of the wreckage.
onetrack is offline  
Old 11th Aug 2014, 13:17
  #11464 (permalink)  
 
Join Date: Jun 2014
Location: London
Age: 59
Posts: 72
I remember spending a day driving around Grand Cayman many years ago exploring all the little beaches and coves. One thing that struck me at the time was the extent to which the waves seem to sort the rubbish into objects of approximately equal size and density.

One small beach we found was obviously the place where lost shoes wash up. Large amounts of rubbish but almost all shoes. That leads me to believe that different components of any wreckage are likely to wash ashore eventually at different places or times depending on size.
Ulric is offline  
Old 11th Aug 2014, 16:44
  #11465 (permalink)  
 
Join Date: May 2014
Location: Canada
Posts: 20
I was invited to speculate. Here's where logic takes us (not very far, I'm afraid, but it's a start):

The idea that a debris field was created in the SIO - and yet the world's collective search efforts have yet to identify a single ounce of it - is well beyond the bounds of common sense.

I concede that the search area is vast and inaccessible, and that, over time, debris sinks, degrades, and comingles with other junk. But all of those things take time; and many items (lifejackets, eg.) retain their visibility, flotation, and evidenciary value for years, so all that would have been needed to positively identify something was a sufficiently vast and hi-def satellite search.

I distinctly remember watching a televised news item about new technology that allowed satellites to read the headline on a newspaper held by someone on the ground. They used "newspaper" instead of "iPad", because the item I watched was broadcast in the 1970's. So I'm going to go out on a limb and suggest that current satellite technology is sufficient to scan quickly for possibilities, and zoom in to identify.

So here are the 3 possible avenues taken by the investigation leadership over the past 5 months:

#1 they decided to withhold this search technology (i.e. chose not to find anything)
#2 they applied the technology, found debris, kept it secret, yet still haven't found MH370
#3 they fully applied the technology, but didn't find debris

#1 requires either irrational search leadership, or the known non-existence of debris.
#2 requires irrational search leadership.
#3 requires the non-existence of debris.

Result: if the search leadership is rational, then there is no debris.

The southern-track-until-fuel-exhaustion hypothesis requires debris (a powerless 777 cannot magically "self-Sully" onto a rolling, roiling ocean).

Result: if the search leadership is rational, then the southern-track-until-fuel-exhaustion hypothesis is invalid.
Wind_Tunnel is offline  
Old 11th Aug 2014, 17:11
  #11466 (permalink)  
 
Join Date: Jan 2001
Location: In the boot of my car!
Posts: 6,000
Wind Tunnel

I don't know why I bother writing anything in this thread as no matter how rational or polite it gets deleted! I must be on auto delete ( That includes the MH17 thread but finding any floating fragments whether life jackets or otherwise from the wreckage will not after all this time give an indication of the crash location.
You are not dealing with just currents and tides but also varying winds over a considerable period of time.

if the Ocean was relatively shallow there might be some small chance of finding static wreckage on the Ocean bed but with the considerable depth and pressure that chance is negligible bar an absolute miracle

Last edited by Pace; 11th Aug 2014 at 17:38.
Pace is offline  
Old 11th Aug 2014, 17:13
  #11467 (permalink)  
 
Join Date: Dec 2006
Location: Florida and wherever my laptop is
Posts: 1,319
Invited to speculate - that's got to be 50% of this thread...

However, look at what happened to the Asiana 777 which hit a sea wall then pirouetted on its nose down the runway then belly flopped back onto the ground. What bits fell off that? The tail cone due to the impact on the sea wall, some undercarriage parts and the engines. The fuselage stayed intact.

So what would happen with a relatively slow and level impact with the water, perhaps following an invented RNAV STAR to an imaginary airport 50 feet above the ocean? I would say the same - the tail may have remained in place without a hard strike but engines may have been lost. But the fuselage could have stayed intact. Engines would have sunk immediately, followed by the fuselage after a few hours. Given 2 - 3 weeks delay what would be still floating? Even if the wings and tail had broken away they may well have sunk. But after floating for 2 weeks or so would be nowhere near the fuselage which itself would not be near the engines which would have sunk close on vertically.

Beach-combing for debris may not be very productive.
Ian W is offline  
Old 11th Aug 2014, 17:36
  #11468 (permalink)  
 
Join Date: Jan 2008
Location: Blighty (Nth. Downs)
Age: 73
Posts: 2,076
Pace,
You and I both...
Quote:
"...finding any floating fragments whether life jackets or otherwise from the wreckage will not after all this time give an indication of the crash location."

No, except that if authentic they would indicate the a/c came down in the ocean.
Chris Scott is offline  
Old 13th Aug 2014, 13:45
  #11469 (permalink)  
 
Join Date: Jan 2008
Location: UK
Posts: 1,519
The idea that a debris field was created in the SIO - and yet the world's collective search efforts have yet to identify a single ounce of it - is well beyond the bounds of common sense.
Nope, your post is well beyond the bounds of common sense. SAR professionals such as myself have tried to explain why it is entirely possible (nay, probable) for a debris field to remain undetected...but armchair experts simply know better.

Hey ho, there are none so blind as those that cannot see.
The Old Fat One is offline  
Old 13th Aug 2014, 14:54
  #11470 (permalink)  
 
Join Date: Aug 2007
Location: sydney
Age: 56
Posts: 356
Its not easy to spot wreckage from the air. Hours of staring at white waves wondering if one of them is something more than a wave. Grey clouds, grey seas, and grey aluminium.

If you want to find wreckage at sea, paint the planes fluoro yellow. White and grey are almost camouflage in poor conditions.

And thats before you consider how large the search area is, and the delay before the search started in the Indian ocean.

Its not always easy to even spot ships from the air. There are numerous WW2 examples of planes missing ships (and even convoys) when they must have passed almost overhead. Pilots from the Ark Royal launched torpedoes at the Sheffield when they believed they were attacking the Bismarck.

Im not at all surprised at the lack of wreckage. Maybe if the fuselage had been breached and lots of bright things spilled out. But a few control surfaces or even a couple of wings would be hard to find, even if still afloat at the time people started looking.
slats11 is offline  
Old 14th Aug 2014, 02:41
  #11471 (permalink)  
 
Join Date: Mar 2009
Location: Perth Western Australia
Age: 52
Posts: 809
Please correct me if its wrong, but my understanding is the FOV of a satellite camera will decrease in proportion to its resolution.

Another words you can see a big area but not small things. Or you can read a headline, but only on a small area (for those that can read headlines). Hence to see the small stuff you would have to know where to look.

The ocean and search area is huge, combined with the fact they didn't get to the "most likely spot until significant time had past means dispersal was even worse.
rh200 is offline  
Old 14th Aug 2014, 15:10
  #11472 (permalink)  
 
Join Date: Jun 2009
Location: LSZG
Age: 48
Posts: 86
Swissair 111 had an undetected fire on board which was initially underestimated. When the fire was detected, by following the checklist, and the pilots did exactly follow the procedure, they were finally unable to control the aircraft and died.

I strongly suggest to listen to the ATC/Cockpit voice recordings. They pilots decided, due to the smell of smoke which was not found, to head to Halifax. But they had to dump fuel. By that time, they did not know how catastrophic the fire was under the hood.

Remember that the MD11 was not having all the sophisticated systems as a B777.

MH370 had a small little SATCOM antenna on the side of the aircraft. The ACARS system is connected to two redundant SafetyBuses systems which have a 28V battery powered, aircraft independant power source. Generators, Bat or RAT are not needed to have the system alive.

There is no CB in the cockpit, like in a Boeing 737. You cannot pull it out just like this.

So, for me ot logical what event would stop ACARS to send information, except a big booom, like with TWA800.
MartinM is offline  
Old 14th Aug 2014, 20:45
  #11473 (permalink)  
 
Join Date: Oct 2007
Location: France
Age: 69
Posts: 136
A new Bathymetric Progress Map of the search area just released:
Progress report

And also a revised version of the report about the search area, with new info:
MH370 - Definition of Underwater Search Areas :
Originally Posted by Update 13 August 2014
Since the public release of the report 'MH370 – Definition of Underwater Search Areas' on 26 June 2014, the ATSB has received a number of queries about some of the technical details contained in the report. The queries have been made directly to the ATSB or through the Chief Commissioner’s blog, InFocus, on the ATSB website.
As a result of the queries, the ATSB is today releasing an updated version of the report to clarify a number of technical aspects. The changes to the report are detailed in the Addendum on the inside cover.
Some of the "queries" are in the comments of this page: Blog - Cautious optimism in search for MH370

Last edited by Shadoko; 14th Aug 2014 at 22:31. Reason: Revised report infos
Shadoko is offline  
Old 15th Aug 2014, 00:06
  #11474 (permalink)  
 
Join Date: Oct 2007
Location: France
Age: 69
Posts: 136
Differences viewed in the "revised version of the report" after a quick look (Old >>> New):
p.02: Jaworkski >>> Jaworski
p.20: Note 16: Complete table of handshake satellite data values provided at appendix X >>> Nothing (there was no appendix X... and it is not in this revised version!). So all subsequent notes are numbered minus 1.
p.32: reference to figure 31 >>> reference to figure 32. It was a typo.
p.56: Table 4 >>> Table 3. There was a mis-numbering.
p.57: Four paragraphes added. From "The reason for the partial compensation..." to "This
combined factor was used to determine the ‘Satellite and EAFC Effect’ in the BFO calculations.
" Have to be read!
p.58: Tables 5 and 6 modified with one line added which explains why the "Downlink Doppler" was changing with a/c latitude (Table 6):
"Uplink Doppler" and "Downlink Doppler" >>> "Aircraft Doppler (uplink)", "Satellite Doppler (uplink)" and "Satellite Doppler (downlink)"

It appears from this revised version that the "Downlink Doppler" was the sum of the "pure" downlink Doppler (which have to be the same for different position of the a/c) and the Doppler from the velocity of the sat to the a/c (the Doppler from the velocity of the a/c to the sat being computed separately). This answers the question of "many"!
Shadoko is offline  
Old 15th Aug 2014, 05:40
  #11475 (permalink)  
 
Join Date: Aug 2007
Location: sydney
Age: 56
Posts: 356
End of flight scenario
Note: Given the imprecise nature of the SATCOM data, it was necessary to make some assumptions regarding pilot control inputs in order to define a search area of a practical size. These assumptions were only made for the purposes of defining a search area and there is no suggestion that the investigation authority will make similar assumptions.
The limited evidence available for MH370 was compared with the accident classes listed previously.
In the case of MH370, there were multiple redundant communications systems fitted to the aircraft (3 x VHF radios, 2 x HF radios, SATCOM system, 2 x ATC transponders). However, no radio communications were received from the aircraft after 1719.29, 7 hours prior to the last SATCOM handshake at 00:19. Analysis of the SATCOM data also showed that there were probably no large changes to the aircraft’s track after approximately 1915, about 5 hours prior to the last SATCOM handshake.
Given these observations, the final stages of the unresponsive crew/ hypoxia event type appeared to best fit the available evidence for the final period of MH370’s flight when it was heading in a generally southerly direction:

Interesting turn of phrase in first paragraph. Obviously it is not the role of ATSB to speculate on possible earlier events. The role of ATSB is locating the plane if possible. The Malaysians are responsible for investigating the psssinlr cause.

Diplomatic protocol would also preclude ATSB from speculating along lines that could embarrass Malaysia.

So ATSB is appropriately not speculating on cause. Yet they had to make some assumptions in order to define the area. Hence the most "neutral" possible hypothesis.

Hopefully the model is not too constrained such that it does not encompass alternative explanations. In particular, the document makes some comments about possible gliding distance if there were control inputs. At 90 odd km, the search areaay not be "wide" enough to cover a controlled glide.
slats11 is offline  
Old 15th Aug 2014, 05:55
  #11476 (permalink)  
 
Join Date: Sep 2008
Location: Where it is comfortable...
Age: 55
Posts: 702
the unresponsive crew/ hypoxia event type appeared to best fit the available evidence
To paraphrase, a conscious but unresponsive and unconscious crew event scenario is indistinguishable, and it had to be one or the other
andrasz is offline  
Old 15th Aug 2014, 06:45
  #11477 (permalink)  
 
Join Date: Aug 2007
Location: sydney
Age: 56
Posts: 356
Yes. But likely quite different profiles after fuel exhaustion. Is 90 odd km sufficient to encompass a glide for max range? I don't think so.

There will have been careful consideration of diplomacy in this document. Also carefully worded disclaimers to minimise any criticism in case of an alternative ultimate explanation. "Hey that was not our responsibility and was not relevant to our role."

It is certain there was very careful consideration given to every comment that even hints at cause in a document of this nature.
slats11 is offline  
Old 18th Aug 2014, 10:29
  #11478 (permalink)  
 
Join Date: Sep 2011
Location: Västerås
Age: 39
Posts: 51
I am wondering about one thing in the definion of the search area report:
Balancing this was the consideration that, by the time of the final SATCOM log on message, the autopilot could have been disengaged for approximately 3 minutes and 40 seconds and the aircraft would have been descending during that period
If the AP had been off for that long, how could the satellite system log on? Doesn't it require a directional antenna? Wouldn't a spiral dive already have developed after 3 minutes, making any directional antenna use impossible? Or is the tracking that quick?

Last edited by sandos; 18th Aug 2014 at 11:35. Reason: Formatting
sandos is offline  
Old 18th Aug 2014, 17:08
  #11479 (permalink)  
 
Join Date: Apr 2014
Location: Albany, GA
Age: 67
Posts: 12
The 777 does not have a steerable antenna for the satcom. There is a low gain and a high gain antenna located on top of the fuselage which look above the horizon.
billslugg is offline  
Old 18th Aug 2014, 21:44
  #11480 (permalink)  
 
Join Date: Jun 2009
Location: NNW of Antipodes
Age: 76
Posts: 1,331
ATSB - Update 18 August 2014

Since the public release of the report 'MH370 – Definition of Underwater Search Areas' on 26 June 2014, the ATSB has received a number of queries about some of the technical details contained in the report. The queries have been made directly to the ATSB or through the Chief Commissioner’s blog, InFocus, on the ATSB website.

As a result of the queries, the ATSB is today releasing an updated version of the report to clarify a number of technical aspects. The changes to the report are detailed in the Addendum on the inside cover.

MH370 - Definition of Underwater Search Areas -PDF: 7.33MB- (updated 18 August 2014)
mm43 is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright © 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.