http://t.co/5FWaYp6T1a This will link you to an SBS visual on how Inmarsat tracked MH370.
This morning, both news.com.au and ABC News (Australia) are reporting that the Malaysian Government has announced that revised data has the last known position of MH370 in the hypothesised ‘southern flight corridor’ – pretty much the middle of the Indian Ocean, west of Perth.
According to ABC News Radio this morning (Australian time) the reviewed data came from Inmarsat who have been auditing their own records.
Inmarsat is a satellite telecommunications company that host data for transmissions aircraft tracking as well as satellite voice communications. according to GMA News, investigators relied on tracking hourly ‘pings’ received from the aircraft along with when the satellite started receiving these ‘pings’, to find a position. This is how they determined the two flight corridors for the aircraft, and ultimately, it seems, the southern flight corridor.
All this indicates that the search under way in the southern Indian Ocean is the likely crash site.
Image credit AMSA.
What theory are we up to?
The more I think about it now, given that the aircraft continued on so far without a change in heading it is my belief that Scenario 2 occurred from my post on March 17, that is:
- Aircraft flies toward destination for an hour
- Flight crew make standard report at IGARI reporting point
- A rapid, intense fire breaks out, affecting multiple electrical systems (transponders go offline)
- Whilst one flight crew member is fighting the fire, the other programs the autopilot to turn back toward Malaysia
- The fire continues until the flight crew are overwhelmed but then the fire goes out
- Aircraft continues on the current heading until running out of fuel, probably over the Indian Ocean
The search is going to continue. Various items that cannot yet be linked to the missing aircraft are beginning to turn up which may indicate that either the ocean is full of floating, large scale rubbish or that the aircraft (or things the aircraft was carrying) are beginning to surface. 2.5 weeks is a long time though. The pieces being found may be well separated from the bulk of any wreckage and the all important ‘black boxes’ or flight data recorders (FDR).
Assuming the recorders are functioning normally, they are required by regulation to transmit for 30 days, though some recorders will transmit for longer.
There is a history of flight data recorders being recovered despite heavy odds. These articles on Air France 447 and South African Airways 295 accidents have good information on search areas and techniques used to locate wreckage and FDRs. Both had large search areas and deep ocean floors.
According to the ABC (Australia) the sequence of events around the time time MH370 blinked off radar screens has been clarified by the investigation team. This new series of events would rule out theory two in my post from yesterday.
Apparently it goes like this:
- ACARS is disabled
- 12 minutes transpire
- Air traffic control (ATC) initiate hand over to the next controller
- MH370 replies with just a “All right, good night”
- MH370 does not make contact with the next assigned controller
- 2 minutes transpire
- Transponders are disabled
- A short time later, the aircraft makes a turn toward land, flies for several more hours and is not seen or heard from again
The Handover process
To help control ATC workload (and factors affecting radio wave propagation) , the world’s airspace is segmented into various ‘sectors’ with an ATC responsible for one or more sectors at a time. As an aircraft approaches the boundary of a sector, the ATC instructs the aircraft to contact the next center by stating the new controller’s callsign (how they are to be addressed) and the radio frequency. The aircraft is required to respond by reading back the frequency. The process is designed so that if the aircraft reads back an incorrect frequency, the error may be detected by the ATC and the aircraft is less likely to have communication trouble finding the next controller. The handover conversation typically goes as follows:
ATC: Generic 456, contact Melbourne Centre, 132.0
Aircraft: 132.0, Generic 456
It is also common for both ATC and flight crews to add greetings and goodbyes as to these handovers but from a technical stand point that is not required and the most important information is the new frequency. In my experience the absence of a read-back is not always a priority from ATC as generally, the crew know the next frequency and are expecting the handover and ATC also know that if they call the wrong frequency they’ll usually come back to the first one and sort any problems out. The trouble with MH370 is that they subsequently disappeared.
What does it mean?
From this latest version of events, if I were the investigation team assigned to investigating the mindset of the crew, I would be focusing on the First Officer at this stage. I say this because systems were being turned off and his voice was heard on the radio (with presumably no struggle in the background) prior to it going missing.
Has anyone done this before?
Yes. There have been many cases (a list can be found here) where aircraft have been used as vessels for suicide. From my recent research, lead causes seem to be trouble with spouses, finance and insurance fraud.