Malaysian Airlines MH370 contact lost
the " I demand to know" brigade..guess what - right now we don't need to know.
I don't believe anyone here is demanding to know the details of "other means." We all surely accept that we won't be told - perhaps ever.
What I (and I think most people share) is a hope and conviction there is more information that will lead to the wreckage, lead to answers, and lead to closure for the relatives. Because the official information that has been released does not create very much hope of this.
I really don't give a damn exactly what this data is. I just hope it is there.
I believe this is the focus of most people here.
Join Date: Jun 2009
Location: in the barrel
Posts: 147
Likes: 0
Received 0 Likes
on
0 Posts
While the media report that Najib Razak has now officially declared the plane as crashed with no survivors, based on satellite data analysis, I still feel uneasy about the whole case.
As far as I understand, actual debris from MH370 has not yet been found and positively identified. In that light, I consider Razak's statement as the most probable outcome, but in no way confirmed.
To me, it appears that due to public pressure and because of the upcoming car racing event, the Malaysian government wants to put a quick end to the story.
A lot of loose ends still need to be tied up.
As far as I understand, actual debris from MH370 has not yet been found and positively identified. In that light, I consider Razak's statement as the most probable outcome, but in no way confirmed.
To me, it appears that due to public pressure and because of the upcoming car racing event, the Malaysian government wants to put a quick end to the story.
A lot of loose ends still need to be tied up.
Join Date: Jul 2013
Location: Dubai
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
MAS statement
"On behalf of all of us at Malaysia Airlines and all Malaysians, our prayers go out to all the loved ones of the 226 passengers and of our 13 friends and colleagues at this enormously painful time".
226 ? or 227 ? souls onboard
"On behalf of all of us at Malaysia Airlines and all Malaysians, our prayers go out to all the loved ones of the 226 passengers and of our 13 friends and colleagues at this enormously painful time".
226 ? or 227 ? souls onboard
Join Date: Jan 2002
Location: Germany (SLF)
Posts: 50
Likes: 0
Received 0 Likes
on
0 Posts
I think there were only 2 passenger airliner crashes caused by mechanical reasons in the past 15 years (China Airlines disintegrating in flight, and Helios Airways loss of cabin pressure). Compare this to 3 pilot suicides during the same time period alone.
Join Date: Jul 2013
Location: Dubai
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
Wiggy I think we do need to know.
Join Date: Mar 2014
Location: CGK
Age: 60
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
Inmarsat calculations
I have been thinking of this. There were hourly pings which can be used to calculate the arcs. Distance between the arcs gives the average hourly speed towards the satellite. Doppler data would give the momentary speed towards the satellite at the moment of the ping. Doppler data would not give too much additional information, but would curtail the set of possible tracks.
Another possibility could be, that inmarsat had ping data from previous flights in their logs. If this data contains signal strength it could be feasible to calculate the radiation pattern of the a/c antenna. If there was a significant asymmetry in the a/c antenna it could be deduced whether the starboard or port side of the antenna pointed to the satellite.
Join Date: Feb 2008
Location: Earth
Posts: 101
Likes: 0
Received 0 Likes
on
0 Posts
As if all the various governments and their militaries don't already know what capabilities there are out there? During this time of tragedy and confusion, classifying everything as a state secret, not sharing data with other agencies/governments or the media, and worst of all the families who are being dragged through emotional roller coaster after emotional roller coaster is all quite ridiculous. We are not living in the cold war where everyone is a spy and every country is trying to destroy you. This emotional scaring of the people who lived through those times is still quite apparent unfortunately. But the past decades it has been to the detriment of the rest of society than some people refuse to drop the us vs them belief.
Keeping Danny in Sandwiches
Join Date: May 1999
Location: UK
Age: 76
Posts: 1,294
Likes: 0
Received 0 Likes
on
0 Posts
"Inmarsat saying they have used Doppler effect to isolate the southern corridor and tested the theory on known flights. Hence their latest conclusion. Can only give a general location."
Some of us on PPRuNe were discussing the probability of that a couple of days ago.
Some of us on PPRuNe were discussing the probability of that a couple of days ago.
Join Date: Sep 2007
Location: Germany
Posts: 152
Likes: 0
Received 0 Likes
on
0 Posts
JakartaDean,
That was my first thought too. But on second thought the single downlink sat -> ground station probably needs as much resources as one link between a/c and sat. To communicate with the a/c the sat has to "illuminate" the whole hemisphere to be receivable by a tiny a/c antenna. In contrast to that the downlink to the ground station can be one concentrated beam and the antenna on the ground can be huge.
Thus the resources spend for the one beamed downlink to the ground station are negligible in comparison to the thousands of unbeamed links to the a/c and ships. So why not use the "cheap" bandwith in the downlink to relay all data available to the ground.
BTW: Newer Aero-C Terminals have automatic doppler comensation. Aero-C - Products - Aero - - Thrane & Thrane
Maybe older terminals required assistance from the satellite for that compensation, which would explain, why the sat "knows" the speed of the terminal.
I have always been sceptical that the logs would contain detailed enough data to estimate speed. Why would a desperate-for-storage-space engineer add logs for such extraneous information? (If she did, hats off as it may have made a difference to this investigation.)
Thus the resources spend for the one beamed downlink to the ground station are negligible in comparison to the thousands of unbeamed links to the a/c and ships. So why not use the "cheap" bandwith in the downlink to relay all data available to the ground.
BTW: Newer Aero-C Terminals have automatic doppler comensation. Aero-C - Products - Aero - - Thrane & Thrane
Maybe older terminals required assistance from the satellite for that compensation, which would explain, why the sat "knows" the speed of the terminal.
Join Date: Mar 2014
Location: Boston ,UK
Age: 48
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
The fire scenario has been mentioned before but if you think about the radar data indicating a climb to 4x000 feet then a sudden dive(Not sure if this information was validated or not)
Is that the move of a pilot trying to extinguish a fire? Has this happened and knocked out a lot of key systems
Is that the move of a pilot trying to extinguish a fire? Has this happened and knocked out a lot of key systems
Join Date: Jul 2013
Location: Dubai
Posts: 91
Likes: 0
Received 0 Likes
on
0 Posts
Nik4Me
I didn't know that.
There was mention of a "flight engineer" in the early stages.
He was Mohd Khairul working in private aviation as a Flight Mechanic.
The "13th" MAS employee onboard was a "Flight Engineer" ?
I didn't know that.
There was mention of a "flight engineer" in the early stages.
He was Mohd Khairul working in private aviation as a Flight Mechanic.
The "13th" MAS employee onboard was a "Flight Engineer" ?
Join Date: Dec 2009
Location: high in the sky....
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Inmarsat doppler
Inmarsat uses 121.5/406.25 MHz tx to find out approximate position using Doppler shift... so why not any other frequency? Accuracy provided by the 406 fx is higher due to the higher frequency and hence more Doppler shift.... I make sense hopefully... or maybe Not...
Join Date: Sep 2007
Location: UK
Posts: 3
Likes: 0
Received 0 Likes
on
0 Posts
Regarding the INMARSAT contribution, this is on their website:
(emphasis added)
It's not clear that what was announced today was anything beyond this?
Washington Post tracks Inmarsat role in hunt for MH370
[...]
The report added that the handshakes from the satellite – along with assumptions about the plane’s speed – helped Australia and the US National Transportation Safety Board to narrow down the search area to just 3 per cent of the southern corridor on 18 March.
[...]
The report added that the handshakes from the satellite – along with assumptions about the plane’s speed – helped Australia and the US National Transportation Safety Board to narrow down the search area to just 3 per cent of the southern corridor on 18 March.
It's not clear that what was announced today was anything beyond this?
Join Date: Feb 2008
Location: UK
Posts: 66
Likes: 0
Received 0 Likes
on
0 Posts
Possible analysis of ping data
A few days ago Capt Kremin pointed out that if the autopilot was in a mode that maintained a constant magnetic heading, there would be a significant turn to the East at the latitudes of Australia due to the large change in magnetic deviation. I looked at this in the context of the modelling that AAIB, NTSB and others are doing, to understand if the differences could be seen in the INMARSAT ping data that it is believed the authorities have. The answer seems to be not, as the two model tracks in the diagram (great circle in grey and constant magnetic heading in yellow) have very similar ping signatures with average differences of less than 15km (r.m.s. error) in the distances for each ping from the sub-satellite point. This may be less than the noise in the INMARSAT data. The two final southerly points of the tracks are 640km apart (one hour South of the last ping arc). Since a single search area was used by AMSA at the start of their activity, some method must have been used to decide between the track options.
Note: The only publically released data point on the map is the red final arc. The other ping arcs (only two shown) are just modelled results showing they match both tracks. The track direction is just an example that roughly matches the data in the AMSA maps.
Note: The only publically released data point on the map is the red final arc. The other ping arcs (only two shown) are just modelled results showing they match both tracks. The track direction is just an example that roughly matches the data in the AMSA maps.
