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 28th Mar 2014, 01:53
  #8421 (permalink)  
 
Join Date: Dec 2006
Location: Not here
Posts: 174
Why are the sateliite photo's

A. in Black and white
B. So bad (definition)
Scissorlink is offline  
Old 28th Mar 2014, 01:55
  #8422 (permalink)  
 
Join Date: Jul 2009
Location: Atlanta, GA USA
Age: 55
Posts: 183
Sheep Guts: The Frequency is 37.5 KHz which is on the Low Frequency LF band 30khz -300khz
Sheep Guts, that in the RADIO SPECTRUM. A ULB's 37.5 KHz is in the AUDIO SPECTRUM. Basically, it's high AUDIO frequency buzzer. Submarines that can tow a mile long antenna and supply thousands of watts of power can use the low frequency radio waves to communicate under water, but the antenna and power requirement isn't practical for an Underwater Locator Beacon in a sunken aircraft.
Coagie is offline  
Old 28th Mar 2014, 01:58
  #8423 (permalink)  
 
Join Date: Mar 2009
Location: Perth Western Australia
Age: 52
Posts: 809
Perhaps the SAR world needs some sort of clearing house, a bit like Chatham House, where information from credible and classified sources can be pooled without disclosing where or how it was obtained. Maybe if this had existed on March 8th we could have saved lives, if there were lives still to be saved.
No SAR goes rather well, they are proffesionel and deal with information given to them authoritys, not media and speculators like on this forum.

It is the only way to go, and yes some of that information will be wrong and will need to change there pattern as more information arises.


The Frequency is 37.5 KHz which is on the Low Frequency LF band 30khz -300khz

Frequency Spectrum definitions and description here
How many times, audio, versus electromagnetic
rh200 is offline  
Old 28th Mar 2014, 02:08
  #8424 (permalink)  
 
Join Date: Jun 2006
Location: Terra Firma
Posts: 161
Bleve:

In alternate nav the CDUs do not have a navigation database. All new waypoints have to be entered by lat/long.
OK I'm with you now. I misread that as 'Alternate Route' ie what some of the ill-informed are calling Route 2. My apologies.
Bleve is offline  
Old 28th Mar 2014, 02:13
  #8425 (permalink)  
 
Join Date: Oct 2010
Location: MD
Posts: 65
Just heard on the ABC that the PM has announced a shift of search assets based on credible evidence.


(for what its worth).
iskyfly is offline  
Old 28th Mar 2014, 02:13
  #8426 (permalink)  
 
Join Date: Mar 2014
Location: Sydney
Age: 62
Posts: 19
Bad photos ...

Scissorlink

The photos are partially bad because nations don't want others to know just how good their cameras are ...
imaynotbeperfect is offline  
Old 28th Mar 2014, 02:16
  #8427 (permalink)  
 
Join Date: Mar 2014
Location: Australia
Posts: 81
I've said this before. The FMC is not required (and Boeing does not have 90 degree options). In a premeditated event the whole scenario can be done on a mobile phone or ipad using an FMC app, then HDG SEL used to navigate by. It does not need pilot training to do that. Just follow the yellow brick (magenta) road. VNAV is the difficult bit.
RifRaf3 is offline  
Old 28th Mar 2014, 02:22
  #8428 (permalink)  
 
Join Date: May 2011
Location: Australia
Posts: 252
I happened to be listening to Oz marine HF frequencies yesterday and seems around every 3 hours there is a pan pan broadcast re MH370 to remind ships entering the area to keep a lookout. Im on the east coast of Oz but the broadcasts were fairly clear.
ChrisJ800 is offline  
Old 28th Mar 2014, 02:23
  #8429 (permalink)  
 
Join Date: Jan 2008
Location: Australia - South of where I'd like to be !
Age: 54
Posts: 4,245
The Media (newspapers in Aus) are saying a major shift in the search area has occurred.


The search area for missing Malaysia Airlines flight MH370 has been updated after a new credible lead was provided to the Australian Maritime Safety Authority (AMSA).
As a result today’s search will shift to an area 1,100 kilometres to the north east based on updated advice provided by the international investigation team in Malaysia.
The Australian Transport Safety Bureau (ATSB), Australia’s investigation agency, has examined this advice and determined that this is the most credible lead to where debris may be located.
The new search area is approximately 319,000 square kilometres and around 1,850 kilometres west of Perth.
The new information is based on continuing analysis of radar data between the South China Sea and the Strait of Malacca before radar contact was lost.
It indicated that the aircraft was travelling faster than previously estimated, resulting in increased fuel usage and reducing the possible distance the aircraft travelled south into the Indian Ocean.
ATSB advises the potential flight path may be the subject of further refinement as the international investigative team supporting the search continues their analysis.
The Australian Geospatial-Intelligence Organisation is re-tasking satellites to image the new area. Weather conditions have improved in the area and ten aircraft are tasked for today’s search.
They include two Royal Australian Air Force (RAAF) P3 Orions, a Japanese Coast Guard jet, a Japanese P3 Orion, a Republic of Korea P3 Orion, a Republic of Korea C130 Hercules, a Royal New Zealand Air Force (RNZAF) P3 Orion, a Chinese military Ilyushin IL-76, a United States Navy P8 Poseidon aircraft, and one civil jet acting as a communications relay.
A further RAAF P3 Orion has been placed on standby at Pearce to investigate any reported sightings.
There are now six vessels relocating to the new search area including HMAS Success and five Chinese ships.
AMSA and the ATSB will hold a press conference at 1430 (AEDT) to provide more details on the new search area.
500N is offline  
Old 28th Mar 2014, 02:24
  #8430 (permalink)  
 
Join Date: Jan 2008
Location: Adelaide
Posts: 87
Just heard on the ABC that the PM has announced a shift of search assets based on credible evidence.
Yes more here.
mmurray is offline  
Old 28th Mar 2014, 02:28
  #8431 (permalink)  
 
Join Date: Sep 2010
Location: Right Here
Posts: 30
The shift to a new search area...is this anything to do with the Thai Satellite of the 300+ objects ? or not ?
Wantion is offline  
Old 28th Mar 2014, 02:33
  #8432 (permalink)  
 
Join Date: May 2011
Location: NEW YORK
Posts: 438
Satellites are poor search tools

Satellites are just as bound by optics constraints as earthbound photographers, so the resolution of an image 20+ miles square is not at the centimeter level. High resolution zooms can be had, but cover a very small field, so the problem becomes telling the satellite where to look exactly.
Drifting debris beneath partial clouds need to be pinpointed by human interpreters, but will have moved by the time that is done. Consequently the searchers cannot direct the higher resolution images a satellite could take fast enough to do any good.
A real time satellite image analysis with immediate high resolution targeting might be available to the military, but none of the commercial earth observation satellites have that. Hence the 2-3 day lag between the taking of the satellite pictures and the public finding of possible debris.
etudiant is offline  
Old 28th Mar 2014, 02:39
  #8433 (permalink)  
 
Join Date: Sep 2010
Location: Right Here
Posts: 30
Moving the search area is a big call ! have they then concluded that objects thus far seen by many satellites are not likely wreckage.?!
Wantion is offline  
Old 28th Mar 2014, 02:41
  #8434 (permalink)  
 
Join Date: Mar 2014
Location: Below glidepath
Posts: 15
There seems to be some confusion on the black box pinger.

The pinger on the black boxes use sound waves at 37.5 kHz, and require sonar detectors, which are essentially sophisticated microphones. Even though this falls in the LF band of 30kHz to 300kHz, the LF designation is for radio, or rf, signals, not sound. 37.5 kHz is ultrasound to us humans.

Sound signals are compression waves - they vibrate the molecules back and forth in the direction they are traveling. Radio, or light, waves are called transverse waves. They consist of an electric, or E field, and a magnetic, or H field, which are both at right angles to each other and to the direction they are traveling.

As they propagate out from a sound source, both sound and radio waves are attenuated by 1/(4*pi*r^2), which is the surface area of a sphere - this is the main reason why sounds or the brightness of lights get weaker the further one moves away from the source. In addition, in water, it appears that sound at 37.5 kHz is attenuated by an additional 0.1 dB/kilometer due to absorption, meaning that sound waves are barely affected by the water. Radio waves at 35 kHz are attenuated by about 6000 dB / kilometer due to the conductivity of salt water, which says the radio wave are essentially totally absorbed.(Underwater Radio Communication by Lloyd Butler VK5BR). This is why they use sound waves instead of radio waves.

However, this does not take into account thermoclines, which, from what I understand, can cause almost total reflection of a sound wave.

Hope this helps.
RichManJoe is offline  
Old 28th Mar 2014, 02:43
  #8435 (permalink)  
 
Join Date: Oct 2008
Location: LAX
Posts: 68
AMSA: Due to a "credible lead", the search area is being shifted 1100 km to the northeast. Press conference at 1430 AEDT to discuss.


http://www.amsa.gov.au/media/documen...70Update23.pdf
mseyfang is offline  
Old 28th Mar 2014, 02:50
  #8436 (permalink)  
 
Join Date: Mar 2014
Location: Below glidepath
Posts: 15
New search area = longer dwells

Moving search area 1100km to the northeast should give longer dwell times over the search area for the aircraft.
RichManJoe is offline  
Old 28th Mar 2014, 02:52
  #8437 (permalink)  
 
Join Date: Jan 2008
Location: Australia - South of where I'd like to be !
Age: 54
Posts: 4,245
Easier all round, less transit, easier / better comms, more time over target,
maybe less tiring on the crews.
500N is offline  
Old 28th Mar 2014, 02:54
  #8438 (permalink)  
 
Join Date: Apr 2011
Location: Cork, Ireland
Age: 50
Posts: 54
Originally Posted by etudiant View Post
Satellites are just as bound by optics constraints as earthbound photographers, so the resolution of an image 20+ miles square is not at the centimeter level. High resolution zooms can be had, but cover a very small field, so the problem becomes telling the satellite where to look exactly.
Drifting debris beneath partial clouds need to be pinpointed by human interpreters, but will have moved by the time that is done. Consequently the searchers cannot direct the higher resolution images a satellite could take fast enough to do any good.
A real time satellite image analysis with immediate high resolution targeting might be available to the military, but none of the commercial earth observation satellites have that. Hence the 2-3 day lag between the taking of the satellite pictures and the public finding of possible debris.
True, but it is not just a question of camera resolution and knowing where to look. Satellites have to peer through the atmosphere and as any amateur astronomer will tell you, this is often like looking through ripples on a pond. Occasionally you get clear still air and then a good satellite picture show clear details like people and vehicles. But this tends to happen in sunny places and high mountains. In the Southern Indian ocean, the waves are rough, the air is turbulent and full of moisture. No matter how fancy your camera or lens system, you won't resolve much better than half a meter.
glenbrook is offline  
Old 28th Mar 2014, 03:02
  #8439 (permalink)  
 
Join Date: Jul 2011
Location: Australia
Posts: 16
Moving search area 1100km to the northeast basically puts it in the Diamantina Deep.

Hard to believe that is a random destination...
JoeBloggs2 is offline  
Old 28th Mar 2014, 03:07
  #8440 (permalink)  
 
Join Date: May 2011
Location: NEW YORK
Posts: 438
1100 km is an hours flying time or more

We have a reasonable indication when the plane ran out of fuel from the satellite pings. Now the belief is that the plane had less endurance than initially expected because its early diversions consumed more fuel than thought. At any possible cruise speed, the 1100 km shift represents more than an hours lower flight time. How does that square with the satellite data?
etudiant is offline  

Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

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