Malaysian Airlines MH370 contact lost
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facts
Have I got this right?
The secondary response disappeared, then primary return disappeared. R/T shut down.....
Did somebody continuously track the a/c after that..who...verified?
So, the a/ may have disintegrated, it may have dropped below radar cover.
Maybe Blind Velocity Speed (unlikely at cruising speed and altitude) or Tangential Fading. (Radar Type in use ?)
So who continuously tracked the primary return?
If it was not continuously tracked it becomes unidentified. Who then re-identified it and how ? A primary return way off the flight planned track ??
I don`t think so.
The secondary response disappeared, then primary return disappeared. R/T shut down.....
Did somebody continuously track the a/c after that..who...verified?
So, the a/ may have disintegrated, it may have dropped below radar cover.
Maybe Blind Velocity Speed (unlikely at cruising speed and altitude) or Tangential Fading. (Radar Type in use ?)
So who continuously tracked the primary return?
If it was not continuously tracked it becomes unidentified. Who then re-identified it and how ? A primary return way off the flight planned track ??
I don`t think so.
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McLaughlin might not have meant that all (eight?) distances (0111-0811) to the satellite were monotonically increasing - perhaps just the final few.
If he did mean that all eight distances were steadily increasing, then to accord with the timings, the number of possible routes likely isn't very large.
If he did mean that all eight distances were steadily increasing, then to accord with the timings, the number of possible routes likely isn't very large.
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I just find it difficult to comprehend, that after 2 weeks, still no sure on where it is.
Surely if they can spot the plate numbers on cars from satellites, then surely they can figure out 370 and it's location, if intact.
Also, once it disappeared, I would like to really know, what and whom the Malaysian ATC, contact immediately.
I think, there is a lot that we are not been told, for some odd conspiracy.
Surely if they can spot the plate numbers on cars from satellites, then surely they can figure out 370 and it's location, if intact.
Also, once it disappeared, I would like to really know, what and whom the Malaysian ATC, contact immediately.
I think, there is a lot that we are not been told, for some odd conspiracy.
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One of the many puzzles I have lies in the (by now basic) assumption that the a/c for some reason 'tracked' along the 40degree Inmarsat arc. Do we not think that would be a remarkable co-incidence?
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Regarding the possible report of reaching FL450.
This was from Primary radar data readings and estimations.
Today at FL380 our actual GPS ALT was 40,300'
So a 2,300' difference, this I've seen on every flight and can be up to 2,500' difference.
It's therefore reasonable that the 45,000' primary radar altitude above sea level was up to 2,500' above the Aircrafts pressure Altimeter reading of FL425 to 430. Hence the A/C wasn't as high as we think?
Not that it matters much.
This was from Primary radar data readings and estimations.
Today at FL380 our actual GPS ALT was 40,300'
So a 2,300' difference, this I've seen on every flight and can be up to 2,500' difference.
It's therefore reasonable that the 45,000' primary radar altitude above sea level was up to 2,500' above the Aircrafts pressure Altimeter reading of FL425 to 430. Hence the A/C wasn't as high as we think?
Not that it matters much.
Good point. Pressure altitude is NOT the actual altitude.
BOAC, either "track" is an area of best probability X nm wide. Depending upon the angular precision, and the number of "degree circles" it may have crossed, the thickness of that band looks to me to get into a few hundred miles either side of the theoretical center. I don't like thinking of those arcs as a "track" but as "areas of probability" that have variation between estimated points/times.
I did a little back of the napkin math. One degree of error or imprecision is in the range of 600 nm.
I am on board with your raised eyebrow regarding such a coincidence.
I did a little back of the napkin math. One degree of error or imprecision is in the range of 600 nm.
I am on board with your raised eyebrow regarding such a coincidence.
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I understand why the pilots need to be able to switch off the transponder in case of malfunction. However, would it be possible to have a secondary transponder on board which would be automatically activated in the event that the primary was switched off? Perhaps the backup could even be battery powered, and could be set to squawk a particular "warning" code. (A warning code indicating there -could- be a problem, rather than an emergency code indicating hijack, etc.) Is there a reason that wouldn't work? It would be unlikely that two different transponders with two different power supplies would both have electrical malfunctions at the same time, so there would be no reason to shut both off.
However, would it be possible to have a secondary transponder on board which would be automatically activated in the event that the primary was switched off?
This makes sense, having two transponders as a measure of redundancy. Large airliners travel in dense traffic control areas in the departure and arrival phases of flight. Having the transponder working so that ATC knows who you are, and where you are, is to me a critical requirement, both for safety and for timely arrivals and sequencing.
Source of Chinese Image
From the Daily Telegraph online
"11.53 Here's the latest information from SASTIND, China's State Administration of Science, Technology and Industry for National Defence, via state news agency Xinhua:
Captured by the high-definition earth observation satellite "Gaofen-1" at around 12 a.m. on March 18 Beijing Time, the imagery spotted the object at 44 degrees, 57 minutes south latitude, and 90 degrees, 13 minutes east longitude, in the southern Indian Ocean, the SASTIND said"
"11.53 Here's the latest information from SASTIND, China's State Administration of Science, Technology and Industry for National Defence, via state news agency Xinhua:
Captured by the high-definition earth observation satellite "Gaofen-1" at around 12 a.m. on March 18 Beijing Time, the imagery spotted the object at 44 degrees, 57 minutes south latitude, and 90 degrees, 13 minutes east longitude, in the southern Indian Ocean, the SASTIND said"
I don't own this space under my name. I should have leased it while I still could
I think most of us realise that the 40 deg arc is an ambiguous position line with a margin of error quoted as up to+/- 50km.
I don't own this space under my name. I should have leased it while I still could
Pedant Mode
Radials radiate. These were arcs subtended by the radial.
Like VOR, is a Radial device and wrongly identified as Range
Like VOR, is a Radial device and wrongly identified as Range
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Actually, thinking a bit deeper, he may have something. Two transponders. One with the usual ATC 4-octal Mode A and another with a discrete aircraft ID. The latter would of course need larger and discrete number or maybe the route identified would suffice. It need not be displayed on ATC screens but never the less recorded in the data store.
The military use multi-mode transponders so the principle exists.
The military use multi-mode transponders so the principle exists.
However who on the ground can see or access that data in the return I don't know.
I don't own this space under my name. I should have leased it while I still could
The difference between pressure altitude and true height is D-factor.
From memory a D-factor in the far east IRO 2,000-2,500 feet was usual.
From memory a D-factor in the far east IRO 2,000-2,500 feet was usual.
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It was the one question I had and it wasn’t until today, buried deep in a secondary article, that this question was answered. A small quantity, all packed, shipped and loaded in accordance with the guidelines. But they were there.
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Originally Posted by oldg
If you are saying you think it flew along those arcs You need to go back and read answers.
Anyway i will tell you those arcs are all the radials from the satellite to the 40 deg range, it did not fly along the arc it could be on anywhere on either one of them.
Anyway i will tell you those arcs are all the radials from the satellite to the 40 deg range, it did not fly along the arc it could be on anywhere on either one of them.
Thank you, Lonewolf - I have always been suspicious of 'co-incidences'. We will share the eyebrows.
Yes, everyone, I do understand the margins of error (as yet unknown) on this '40 degree arc', but I still reckon that the odds of the a/c tracking ACROSS the arcs and at least one ping being at some other angle would be high.
Are we to assume from the sketchy info so far that the 'elevation' of the first ping after comms loss (supposedly Malacca) was the same as the previous (north of Malaysia?).
fg - thanks for PM - don't forget we (some) are assuming the a/c WAS on that arc when it supposedly crashed - co-incidence?
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Should planes be fitted with something like this in an 'inaccessible in flight location' (maybe on the tail fin) http://www.globaltelesat.co.uk/satph...Messenger.html
It's a GPS tracker that can report it's position by satellite every few minutes (5 / 10 minutes would probably be good). Would probably also be useful for oceanic ATC.
[I am aware of the project to have satellite based ADS-B recievers]
It's a GPS tracker that can report it's position by satellite every few minutes (5 / 10 minutes would probably be good). Would probably also be useful for oceanic ATC.
[I am aware of the project to have satellite based ADS-B recievers]
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The assumption it would have been seen (transponderless) on most radars is wrong too. All explained earlier if you look back far enough.
The 'gap' in the arcs is because they commence at LKP.
The 'gap' in the arcs is because they commence at LKP.
If you think mil radar will not pick up unidentified planes please explain why they have them!
Last edited by oldoberon; 22nd Mar 2014 at 17:13. Reason: change I to it
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A very valid point, why would anyone navigate along a route exactly the same distance (elevation) from a satellite?
Almost any route of any distance, great circle or compass would cross "arcs" as you say.