Re: Any pilots that actually KNOW?
I am qualified on a large aircraft (not the 777) and fly overwater routes in both the Atlantic and Pacific regions (mostly the Atlantic by choice). The 777 is a big airplane, but it's a mere speck compared to an ocean.
I'll try to answer a few of the questions posed in this thread.
1) Radar. It's good out to about 160 miles or so for an aircraft at 35,000'. Its distance capability decreases with altitude. At 500', it's good for about 20 miles, depending on antenna site and other factors. Those figures are for an aircraft equipped with an operating transponder. For "skin painting", those figures would probably be somewhat less. I just really don't know because I have no experience with such and hope to never gain it!
2) Transponder. It really doesn't have an "off" position. It is placed in "standby" which has much the same effect. There is a circuit breaker for it on my aircraft. Wire cutters would be useless to disable it. There are no wires accessible.
3) ACARS. Aircraft Communication Addressing and Reporting System. The best analogy I can draw for a layman about what ACARS does and how it operates is "text messaging". It communicates with the ground via VHF or HF radios or via Sat Comm. In my operation, we communicate with flight ops, get weather reports, receive ATC route clearances on the ground and oceanic clearances airborne prior to making an Atlantic crossing. ACARS on my aircraft also makes use of a utility called a Digital Flight Data Aquisition Unit (DFDAU). It's a system intalled on the aircraft that collects myriad performance parameters and sends them to our company automatically on a periodic, but not continuous, basis via ACARS. I'm certain the 777 had ACARS and DFDAU. I don't know the specifics of its operation.
This incident certainly is a mystery.
