[lb1lf]

>Or just continously upload the data to the internet, should be quite feasible these days with satellites everywhere.

That would probably be a bit too much for existing satellite communication systems; while most flights wouldn't need to transmit such a signal most of the time (If a plane went missing over, say, the Midwest, we'd find it!), frequent transmissions from every flight over sea, for instance would probably overload today's networks - meaning you'd need to launch new satellites to provide this service, meaning it would be outrageously expensive, meaning it wouldn't happen.

However, if we relax the requirement to, say, once every five minutes or so, at least you'll have a much better idea of where something went down than 'Probably somewhere in the southern hemisphere.'

[nikanj]

A quick googling tells me there are about 10000-15000 planes in the air around the world. GPS coordinates take less than 100 bytes, but let's give some headroom for plane ID, timestamp, etc.

That would mean about 1.5 megabytes per minute, globally. I think the global satellite network is easily up to the task.

[lb1lf]

The raw data rate is pretty low, but keep in mind that there's all sorts of signaling traffic going on just to establish a connection, depending on protocol requiring multiple transmit/receive cycles - which in turn means waiting. Again depending on protocol, you may also have to handle collisions (more than one transmission in the same channel at the same time) etc - while still maintaining service for the network's regular customers.

Multiple short transmissions are more taxing than a few long ones.

[cm2187]

Over the midwest, the chances of survival are much greater than in the sea. Finding the wreckage immediatly is even more critical.

Would a GPS coordinate every minute really be such a strain on the systems?

[msandford]

Make it every 5min or 15min and most of the technical problems drop right out. And it's still super useful for this kind of thing at 20% or 7% of the bandwidth.