In part 2 of my 12th anniversary series "Imagining the Impossible," we interrogate Inmarsat's certainty that their data couldn't have been tampered with
It also seems that the sdu being turned off and on indicates sabotage. Someone must have had a reason for doing that or the sdu power was on a bus that shut down other systems. When the sdu comes back it is missing flight identifier info which indicates some change to the system. I still think you need to consider the security of all possible points of data manipulation, including a hack of Inmarsat data.
Yes, I agree completely, the reboot of the SDU is deeply strange and suspicious. A lot of people have spent a lot of time trying to imagine a situation in which a suicidal pilot would isolate the left AC bus in order to accomplish something, and it so doing turned off the SDU as well. IMO none of them make any sense. As far as considering all possible points of data manipulation, I'm all ears, but unfortunately no one has come up with a description of such a scenario.
Interesting that the 629 is involved in the investigation. The 629 uses set timing intervals for each device on the bus. Flight has priority. Talking to a satellite is low on the list. Might affect the signal speed through the system.
Yes, it's the main digital data bus on the modern Boeing aircraft. I was manager over the FETS system that used the bus to control the inputs to the cockpit so the pilots could check the system operations realtime on the airplane itself. This system proved to be more accurate than the iron bird used for initial testing. The 629 uses a timing table to allow access to the bus. Every unit on the system is assigned a time to jump on. Flight gets early times other systems get later times. This is so units don't trip over each other.
I may be the only person able to determine the location of the plane crash…
I have the ability and skill, but my voice will not reach them unless they have the ability to meet
Unless they have the ability to meet what?
It also seems that the sdu being turned off and on indicates sabotage. Someone must have had a reason for doing that or the sdu power was on a bus that shut down other systems. When the sdu comes back it is missing flight identifier info which indicates some change to the system. I still think you need to consider the security of all possible points of data manipulation, including a hack of Inmarsat data.
Yes, I agree completely, the reboot of the SDU is deeply strange and suspicious. A lot of people have spent a lot of time trying to imagine a situation in which a suicidal pilot would isolate the left AC bus in order to accomplish something, and it so doing turned off the SDU as well. IMO none of them make any sense. As far as considering all possible points of data manipulation, I'm all ears, but unfortunately no one has come up with a description of such a scenario.
Interesting that the 629 is involved in the investigation. The 629 uses set timing intervals for each device on the bus. Flight has priority. Talking to a satellite is low on the list. Might affect the signal speed through the system.
That's interesting. So you're familiar with the ARINC 629?
Yes, it's the main digital data bus on the modern Boeing aircraft. I was manager over the FETS system that used the bus to control the inputs to the cockpit so the pilots could check the system operations realtime on the airplane itself. This system proved to be more accurate than the iron bird used for initial testing. The 629 uses a timing table to allow access to the bus. Every unit on the system is assigned a time to jump on. Flight gets early times other systems get later times. This is so units don't trip over each other.
Just sent you an email... we should discuss!