Now the Aussies claim to have found what appears to be wreckage.
In fairness, I don’t think that they Aussies are saying it is wreckage. They are simply saying that there is something unusual there and it’s big and thus worth checking out to see if it is wreckage.
That article from Wired, which has gone viral now, appears to be debunked here
One thing I saw in Immarsat’s TV appearance the other day was a diagram showing what are obviously spot beams – just like Thuraya’s 128 spot beams. This means the satellite operator knows where the signal is coming from – within a radius of a few hundred miles. For example when I landed at Shoreham from the IOM, my Thuraya phone was still showing “Thuraya Isle of Man”. This is in addition to the GPS coordinates which are a required part of any satphone data transfer session (for NSA etc surveillance reasons, as much as anything else) beyond the initial connection setup.
However that would be too obvious, so these “pings” must have been just transmissions from the aircraft which got picked up by some other antenna on the satellite.
I bet there will be changes in the business very soon – whatever the outcome of this accident. They will probably make satellite position reporting mandatory. According to one report, Immarsat charge $2 per report, which is $4/hr. How many airliners are airborne at any time?
From the RTCA DO that specifies how the TSO ELT-AF (Automatic Fixed that is the one that is attached to the rigid structure, usually in the tail or rear fuselage) is to operate:
Remote controls, if installed, shall provide the “MANUAL ON,” “ARMED” and “RESET” modes. The “RESET” control must have a provision to prevent an inadvertent reset.
There shall be no “OFF” mode.
The ELT-AF itself has an ON/OFF switch and the power is solely from the attached battery so there is no circuit breaker. The ELT-AF is not mounted where it can be accessed by the pilot.
Airlines may have multiple ELT-AP (Automatic Portable) units that are not crash activated and can be activated by the pilot or cabin crew. These are more like a PLB. They are also expected to be included with each raft.
For example when I landed at Shoreham from the IOM, my Thuraya phone was still showing “Thuraya Isle of Man”.
The Thuraya XT does not update its location display unless you restart it.
On the 7100, there is certainly a delay in changing over the region display, but on longer trips (say 800nm in one leg) I have seen it change over.
The 7100 was designed and made by Hughes. The later models are all Chinese. At one stage I found the company that made them – the bluetooth [in]compatibility certificate is in their name. Anyway that’s digressing. It’s interesting that Immarsat did not use the spot beam system to locate the aircraft because that would have avoided that whole bull about whether the plane flew north or south.
I can guarantee GPS position transmittion will be mandatory from now on, and not just every 30 mins.
How about ADS-B? I know Europe is just a tiny place really, but I saw a Eurocontrol demo of one receiver in Brussels picking up every airliner flying in Europe. Surely this plane would have been emitting ADS-B the whole time?
Some interesting reading in the context of missing aircraft: Missing Aircraft 1948-2014
How about ADS-B? I know Europe is just a tiny place really, but I saw a Eurocontrol demo of one receiver in Brussels picking up every airliner flying in Europe. Surely this plane would have been emitting ADS-B the whole time?
Not if you turn off the transponder.
NCYankee is right as usual
No OFF switch. Also no CB to pull.
Some interesting reading in the context of missing aircraft
Interesting indeed, although a lot of those date back to the days of dodgy navigation i.e. before the 1970s for transatlantic jet ops, and before the 1990s for most other aircraft. In much of the world, if you got lost, and ran out of fuel, nobody might ever find you.
Not if you turn off the transponder.
That will be changing soon, I am sure…
Or mandatory satcom reporting.
ADS-B isn’t going to be any good in remote areas anyway. The US (etc) spy satellites can definitely pick up ADS-B anywhere in the world if they want to, but
I think if I contorted my arm while seated in the pilots seat I could turn off my ELT – the unit itself is installed directly behind the passenger seat. The remote switch is obviously easier to reach and in that way it allows me to inadvertently actuate the ELT every couple of years. 
ADS-B isn’t going to be any good in remote areas anyway. The US (etc) spy satellites can definitely pick up ADS-B anywhere in the world if they want to
There is an ESA satellite by the German Space Agency DLR which records ADS-B data. It was put in operation in 2013.
