How does the satellite link on the aircraft know to switch from the IOR to the POR satellite. Any sat wiz kids can tell me how it works? Is it signal strength from the Aircraft or is it signal strength from the Sat itself and then send a handshake change Frequency instruction? If this handshake change freq. instruction is not decoded wouldn't it keep talking to the IOR sat and not the POR one. If this is the case then the omitted 40 degree rings need to be joined again. Which incidentally is right over the airways and initial suspected area of the original search in the South China Sea. Which incidentally hasn't be totally covered by either Nation or agency. Now it is going to be cut short.
Also the other pings in between 01:07am and 08:11am have not been disclosed to us yet.

Is there someone out there who can tell me how Immersat works?

I feel like the people still posting about the possibility of technical failures causing this incident are clutching at straws. Given the comms going off at seperate times and the waypoint flying, surely there has to have been a non-hypoxic human being at the controls.

Also, can't see the motivation for a terrorist group to hijack this particular flight unless they were targetting KL, and from direction plane went, that doesn't seem likely. The theories like the aircraft being hijacked and used to fly into the Hague or another target at a later date make no sense. Why complicate matters by hijacking a plane in KL to commit an act of terror thousands of miles away? It's the equivalent of the 9/11 terrorists hijacking planes in Brazil to eventually attack NYC.

Inside job by member of crew seems to fit the facts so far, but still has plenty of flaws.
If suicide, why not crash the plane immediately? If trying to hide the suicide by crashing in deep ocean, why fly waypoints? An experienced pilot would know that would lead to suspicion falling on crew.
If politically motivated, say Captain Shah hijacking over Anwar Ibrahim verdict, why has there been no note or message explaining actions? If someone was motivated by anger over the trial, they would want the media/public to know the reasons for their actions. One possible explanation for the confusion and red herrings over the past week would be that a document taking responsibility and explaining political motivation was in fact found early on. The Malaysians could have attempted to cover it up to avoid political embarassment and been foiled by pressure from US and others. Wild speculation, I know, but something about the Malaysian government response seems a little strange, more than just garden variety government incompetence.

Indeed, that would tell us if the aircraft was flying in circles or a roughly straight line.

Well, can you give us the coordinates then? It will sure make things a lot easier for the Search And Recovery teams because at the moment they don't have a clue. And what's the condition of the FDR and CVR? Is it in good nick? :rolleyes:

@ p.j.m - don't give up the day job. You won't cut it as a super sleuth.

"reportedly the Greek ship "Elka Athina 'interests shipowner Karnezi took position on the existence of objects at sea in the Straits of Malacca!

Specifically, a few hours ago got a message from a coastal station of Indonesia with*position: width 0551 length 09657.5 northern and eastern that found in suitcases belonging to passengers probably fatal flight of Malaysia Airlines.

Master of Elka Athina is Dimitris Zampelis and second officer Dimitris Karagiannis.

Department news defencenet.gr"

p.j.m. states that a previous posting mentions nothing about debris in the Malacca straits or a greek ship

True, but if you look at the google translation of the referenced page:
Google Translate
under related news it contains a link:
To ship "Elka Athina" received Stigma suitcases belonging to passengers of Boeing 777

Regards, Peter

To me, this is looking more and more like a Helios event, where the aircraft entered a hold for hours on a waypoint above the Malacca strait with no one conscious at the controls... My guess is the satellite ping "arcs" are miscalculated and a bit of a red herring.

XPDR SWITCH
 

"I can think of no reason you would EVER want to turn off the transponder once in flight, and I think that we will find this option is rapidly removed from the flight deck.. "

The time mine started squawking 7600, despite what it was set for, in the YYZ control zone comes to mind

Malaysian Airlines MH370 contact lost
 

As ve3id said. You need the option to turn it off for spurious transmissions/failure. Your transponders are also covered by the MEL (both if the route doesn't require it or coordinated with prior notice)

So ... bottom line.
The daylight has gone in the area now...another full day of searching and nothing we are being told about... officially.
There is talk of a Greek freighter picking up debris in the Malacca Strait.
It will be a random discovery that will finalise the location.

Greek news sites posted that :

The greek oil tanker " ELKA Athina " received orders from indonesian station to investigate at Latitude 0551N and Longtidude 09657,5 Ε (malaca straits) suspect things that they look like suitcases. The ship is 3 to 4 hours away from the indicated point.

http://www.tovima.gr/files/1/2014/ploio.png

Marine traffic's track for Elka Athina does at least tally with the location for this- note the track ends yesterday unless you have a paid sub:

https://www.marinetraffic.com/en/ais...bf40a08225fef2

See ELKA ATHINA Current position (IMO 9249116) - Vessel Finder

Re Daily Mirror "expert" claiming the plane was hacked..
 

Rent-her-as-an-expert-on-any-disaster...
She's your expert..
From hailstorms to the Chilean miners.

Disaster doctor on call in London | Toowoomba Chronicle

Not sure her doctorate in economics is really something that qualifies her to comment on how this plane was taken over.

Still, the Mirror has engaged her. Hopefully on an exclusive basis so that she stays away from any sensible outlet.

Tracking an aircaft
 

The older days (pre 406.25 MHz) the position of downed aircraft was with the the Doppler shift of 243MHz signal,,, if my memory serves me right... It was done by INMARSAT satellites in conjunction with Local user terminals... if a stationary crashed aircraft position can be located than why not a slow flying one?

So we can easily find the position of the ship which might possibly find the plane which we cannot find?

cvr
 

"CVR would record the last two or three odd hours... the initial part is overwritten... earlier they'd use a continuous tape, nowadays they use solid state devices...In the present context the CVR wouldn't have anything from the early part of the sortie..."
Strange limitation to have persisted despite the advent of solid state technology and secure data transmission possibilities.

Snowfalcon,

The geostationary point in the Sputnik case was the observation point on the ground. In this case, it's whatever observation birds picked up the transmissions, be they sat datalink or otherwise (radalt, weather radar etc)

Go into the login pages of your aero-I or aero-h system and most have Doppler listed.

Doppler analysis (analysis of the signal frequency and it's shift) doesn't need a continuous login, it needs the same ping to be sampled by 2 separate satellites, whether they are national assets or part of the satcom network, matters not a jot.

http://en.wikipedia.org/wiki/Transit_(satellite)

The confusing thing about the Greek tanker development is that there are clearly other vessels that are closer to the quoted coordinates when looking at up-to-the-minute vessel tracking data.

I imagine this is just one of numerous potential sightings that vessels in the area have been tasked to look at, except someone on this ship, or someone a crew member has spoken to, is a bit more social media savvy or connected to the outside world than your average salty sea dog, and so this particular tasking has landed on some journo's radar.

Turnback point Engine issue
 

A Question for Engineers and T7 pilots

Given that

1 Malaysian police said there were witnesses on the coastal area near the turnback path of MH370 who saw a/c lights and heard a loud bang

2 an oil rig worker (on the oil rig Songa Mercur, off south east Vietnam) ( about 360nm from turnback point saw a “burning in the sky in the direction of the plane for 10 to 15 seconds,

3 Compressor stalls can be transient and intermittent or steady state and severe. Indications of a transient/intermittent stall are usually an intermittent “bang” as backfire and flow reversal take place. If the stall develops and becomes steady, strong vibration and a loud roar may develop from the continuous flow reversal. Quite often the cockpit gauges will not show a mild or transient stall, but will indicate a developed stall. Typical instrument indications include fluctuations in r.p.m., and an increase in exhaust gas temperature. Most transient stalls are not harmful to the engine and often correct themselves after one or two pulsations.
Turbine engine thrust varies directly with air density. As air density decreases, so does thrust. While both turbine and reciprocating powered engines are affected to some degree by high relative humidity, turbine engines will experience a negligible loss of thrust. (US Private pilot ground school source)

Can the "sound and light show” at turnback point be explained by the above?
Can pilot perform such deliberate aerobatics in the lower reaches of the stratosphere for whatever purpose and recover?(Radar signals recorded by the Malaysian military appeared to show that the missing airliner climbed to 45,000 feet (NYT).