Originally Posted by
iakobos
Satellite aerials are not omni-directional
Stricto senso this is incorrect.
Eg. Iridium, Orbcomm, Globalstar, Thuraya are satellites or constellations of satellites that are accessible by portable equipment with rubberduck type of antennas.
What matters is frequency band (L, C, Ku or Ka), what it is aiming for (in terms of bandwidth/speed, which correlates to satellite power and antennas' gains) and type of orbit and height (LEO, MEO or GEO, which correlates also to latency, a critical factor for some applications).
iakobos,
Stricto senso you are right.
Which is why I said it's "technologically possible".... I already was thinking of that.
But none of those systems are capable of handling thousands of 100 kbit/sec data streams simultaneously,
reliably.
And try to hold the rubberduck (I am familiar with the type of antenna) upside down under an aircraft and see what ERP you get towards the satellite(s) you are relying on for those last critical seconds/minutes of data.
Something passed through my mind...
Twenty-five years ago, being able to flip open a little 'StarTrek'-like communicator open nearly anywhere in the world, an talk to nearly anybody else on the planet, would have seemed a pipe dream. (Admittedly, there are still places where you need a sat-phone, but I think you get my point.)
Now it's almost normal.
Twenty-five years from now, we'll probably expect to be able to plug in our little communicator on a plane anywhere, and instantly get connected to anybody else on the planet.
FDR, CVR and a lot of other data could ride piggy-back onto such a service.
But while FDRs and CVRs now are slowly and steadily becoming mandatory on ever smaller aircraft, even if not not on your Cessna, how many of those "data transfer" systems would in in place (and not part of the MEL) even then?
Let's stick with FDRs and CVRs (and VCRs if they can be shown to be useful) powered by the essential bus, that will stay with the disaster until the last possible second.
CJ