Those 'Pings" again.
 

To the best of my knowledge the Inmarsat I-3 series satellite at nominal position 0° 64°E had logged the unique ID of this aircraft when the SATCOM was activated prior to departure Lumpur. The Satellite checked hourly that the bird was still in range by 'pinging' it. The return time of the signal originated by the SAT and acknowledged by the aircraft is the means of creating a position line (in this case a curved one) that is being used to determine the radius of a circle on which the aircraft could be. This whole procedure has been explained in many posts to this thread, and the Professor should at least get his facts right.

The basic explanation can be found on -page 297 Post #5935
and an example showing the possible 180°M heading is on - page 299 Post #5971

The BBC seems to be reading PPRuNE, and its a pity the professor hasn't.:ok:

Only ONE satellite is involved.

Wawa: been to NG737 school as an avionics tech. No direct hands on in a 777. In general most boxes have 2 different buss inputs. Not so say it couldn't happen, but sems way out there. And you would get error messages on the EICAS.

In retrospect, it the pings included basic lat/long info, just degrees and min. We wouldn't be so lost at this point. And the satcom needs it to point the Antenna anyway. 10 bytes once an hour...:(

Try www.skyvector.com -- it has global high altitude charts and a flight planning function that enables you to compute leg distances. Input WMKK-ZBAA into the base flight track, then drag the track line over the asserted waypoints. Bearings and leg distances will be computed and you'll be able to see how they match up with the FIR boundaries.

ETA: Let's see if this works. Link to map here: http://skyvector.com/?ll=5.687414242...VAL:F.VO.IGREX

Tried to post an image, but the link works. Times are based on an assumed 462 knots i.e. M= .80.

Map of data
 

I have put together a map of the known bit of info
MAS370
I have marked up the flight plan, the three named waypoints mentioned by various sources and confirmed by Malaysian authorities, the Inmasat angle ranges and the final 40° line.

I have added the known points of info we have, last radio transmission, last acars, last primary radar return, based on their timing and then joined the dots a bit from the last known point to waypoint GIVAL. Comments by the Malaysians say it tracked towards VAMPI, but not over VAMPI.

Based on the last known radar point 200 nm of Penang gives us a gound speed in the range of 420 knots. If I stretch the last known point to 250 nm of Penang it comes back at about 470 kts which I think is more reasonable. The last GS from Flightaware had it at 468 kts.

The possible flight paths are my own supposition, it had to get from the last known radar point at 0215 (local) to the 40° inmarsat intercept at 0811 (local) so the lines reflect approx positions based on a number of ground speeds.

Will they release the ping data today?

A "join the dots" plot is not possible from one satellite. There would be several full circles, one for each ping, no dots. Parts of each circle could be eliminated but an exact plot would be impossible from the ping data from only one satellite.

This is the unfortuate truth of the matter. If a second satellite was involved two connect the dots plots could be made, one to the north the other to the south in a mirror image.

If a third satellite was in line with the first two it wouldn't help anything but if it was off the line to the north or south it would pinpoint the exact location.

ReadMyACARS
 

ReadMyACARS...that is very astute - assuming they took the southern arc.

:D

The very sobering incident of Egyptair Flt MS667
 

On July 29 2011 an Egyptair 777-200 Flight MS667 Reg SU-GBP was preparing for departure at Cairo Apt and had just finished boarding when the cockpit crew oxygen system malfunctioned and started an intense fire on the RHS of the cockpit.
Everybody evacuated safely through the still-connected passenger bridge through doors 1L and 2L, and the fire was brought under control by the airport fire dept but not after melting huge holes in the exterior acft skin and causing severe damage to the entire fwd section of the plane.
The accident report in the link above is a very sobering read if you imagine the incident happening 60 mins later as the 777 has departed and at altitude.
There would be no time to talk to the ground, and very little time for the crew to effect a descent before smoke/heat/depressurization took everybody out

@intel101 ...or it could mean that there are unidentified radar echoes (from drone overflights and whatnot) frequently enough for them to ignore those that don't seem to pose a threat...

There is a Global Hawk base not far away, afterall.

@Readmy ACARS.

A lot neater than my google earth version which is not suitable for public viewing.
You might want to look at the due south assumption which appears to come from the NTSB. That along with the 08:11 range and assumed ground speed might confirm start points for the plot.

More compelling reasons in my view are that OZ public prefer its government does something i.e. "have a go" to find its six Aussies and the rest of the passengers, rather than appear to wait for more conclusive information.

Also there was a Chinese registered vessel ALREADY in the area at the time the search was announced and the SAR could monitor it.


ABC noon news interviewed Aussie Jeff Askew ex Group General Manager Security and Emergency Management at Qantas for 15 years, and formerly with police and defence and Australian Airlines, he now runs a consultancy company, with a "top secret" clearance.

Summary;
He says they probably will find the plane, it may take time.
He couldn't answer questions about Pine Gap but says they wouldn't hold back info.

Last two weeks public have learnt it is more difficult to find a plane than previously thought, the capability is not there.
Says this incident will have ramifications to airlines and manufacturers. Will be driven by what is found to be facts.
Changes could be to airspace management and broad security of it including passports.
Live tracking of flights, passenger screening, change to looking for bad people not just bad things.
Airlines will need to manage threats from inside (pilots) and greater cargo security.

Industry has understood these issues, but were not at forefront of thinking.
Pilots should not be able to close down transponders, so fire issues will need to be addressed.

Says Malaysians Airlines did the best they could then other agencies took over.

@ ReadMyACARS / Map of Data
 

Great map. Just had one query. Bearing in mind the Indonesian denial that MH370 crossed their airspace:

MH370 not detected by Indonesian military radar: Defense minister | The Jakarta Post

Does that infer that more turns were made before hitting 'open water'? Or do you think that the current path is far enough away from Indonesian primary radar capabilities (whatever they are)?

Heli, the 'mirror image' is only a result of the arc(s) being drawn about the equator. The arcs are actually part of a Position Circle with one segment already eliminated by non reception by the adjoining satellite, and actually a second one (through Africa) outside the max range of a great circle track from the last radar fix, also eliminated.
The 'dots' would be the running fix on each later segment or arc, out from the centre, but note there would be two on any hourly range circle centered around each prior fix, being the circle intersect points along the next arc. Note that later arcs can be inside earlier arcs if the thing had done 180's. The area would actually grow in tree branch fashion.
The test of validity would be a feasible set of points along the final arc. Its a DR nav solution.

lakedude; look up 'running fix', with a radar fix near an early ping as a strart point.

Jindalee OTHR
 

Jindalee is an OTHR using High Frequency transmissions determined by an FMS A frequency management system.
It has three main lobes.
But only one transmitter with a steerable beam at a secret location.

The time of the alleged transition of the Malaysian flight, it has been suggested occurred off the beam when the radar beam was looking North.


Debate will occur as to if any HF OTHR operating in the 17-24 MHZ band would have propagation at that time of day/night.


And why ask Jindalee why not ask the Russians and the UK one on Cyprus and all the other OTHRs operating at the time,


To find out if you had HF prop between central Australia and Malaysia...
You would need the sounder data from Xmas island, but it would be easy using IPS charts on the day to see the MUF on the NW path to see if the OTHR would have produced a paint, which would be just a dot and have to be correlated with other radar data from Malaysia to join the dots.
I think if the RAAF have data they have given it to their Orion pilots and it maybe the reason why the search area has been narrowed slightly.


I still ask the question (please don't shoot the messenger) if the aircraft was under pilot/hijacker control, how did the people involved control 200 passengers for 7 hours going into daylight over vast expanses of ocean.
When it would become obvious that they weren't going to China?


As in Boston a few passengers could easily overcome the person guarding them and the longer the standoff went on the more determined the people would become to find out what was going on and try something.




And so far no one on board appears to be a radical...bent of self destruction 3000km out in a remote ocean. what would be the point?

Hand Off Frequencies Question
 

Was VHF used in the Gulf of Thailand during the hand off or was it HF?

The blog post linked to by marlin was rather unimpressive IMO.

The writer of it ought to bear the following points in mind:

(a) The Indian radars covering the Andaman Islands may not have been on during the night because it was "too expensive" according to some reports recently.

(b) Also, there ought to be more coordination between different countries. You could have a situation where a plane hijacked by terrorists cleverly flies along the air borders between, for example, Malaysia, Thailand and Indonesia and none of those countries scrambles its fighter jets because they each think it's not in their territory, flying in the other direction, and "not a threat". The plane could then change direction at the last minute before an attack.

Think we all know that except the good prof.

However like many have said on here ian_W and I thjnk yourself and others there must be ways to extrapolate some date out of the missing ping data basesd on the spacing (range between them, estimated speed etc and if looks as if the experts have done it.

should have released it who knows perhaps ppruners would have come up with an answer earlier

Thanks for the feed back, sorry it too 6000 message befoe I got there.

Apparently Jindalee wouldn't have picked it up,for one it might not have been on and another it apparently is used to concentrate on areas for periods of time.

Some years ago I heard the claim, not refuted, that no civilian had ever actually seen what Jindalle produces. So we really don't know.

The reason I took the aircraft out to BEDAX was so that the Indonesian radar wouldn't have seen it. Again, I have to make a presumtion that the radar at Lhokseumawe was not capable of primary returns or it didn't have the power. All the circles on the map are 60 nm, but, depending on power they shoud be capable of much further than that.

I'll have a look at the due south idea, because that was actually my first thought, the pilot took it to a certain waypoint and then headed south.

@marlin

Thank you. This is my suspicion since a long time. The malaysian air force did not scamble because it was an identified track. They had never lost it but marked as civil, friend or whatever is their denomination. Now I would love to see the track plot from their air command system published for the exact track the aircraft took.

The indonesian radar did not pick it up because it never went that far!

Marlin: "Why the Malaysian fighters were not scrambled"
 

Aha...nothing like a poke in the eye with a sharp stick to provoke a response and when you filter out the understandably indignant adjectives at:

MH370: I Speak Out | The Crap In Between SeaDemon's Ears

what is left reveals a fairly close correlation with the path proposed by "Read my ACARS" at:

MAS370

Which is an excellent piece of deduction.

Am guessing that the new radar data likely came from the Andaman Islands base which is why the donor wishes to remain anonymous.