[jellicle]

If the internet is to be believed, the Iridium network has a total capacity of 172,000 simultaneous users (if every satellite worldwide is fully utilized).

There are many figures citing 5,000 planes in the air over the United States at any given time. But especially for a tracker, you'd want to leave it on all the time the plane is turned on, so many of the planes on the ground would need to be tracked as well.

My guess is that, particularly for the U.S. and Europe, putting planes on the Iridium network would exceed the total capacity of the system all by themselves, even if there were no other Iridium users.

This is not a trivial problem to solve.

[TeMPOraL]

Thanks for the actual number. It seems though that 172 000 refers to simultaneous voice users. I was thinking about their data services - planes could send short bursts of location data (couple hundred bytes at most) every minute or three.

I agree it's not a trivial problem to solve, but it looks solvable.

[mcculley]

I agree that this seems easily solvable. We use SPOT Trace (http://findmespot.com/en/index.php?cid=128) units on offshore tug boats, as do many in the shipping industry. These periodically send their GPS location back via Globalstar. It seems to me that if a passenger jet can be approved to install satellite TV receivers, it could be approved for these.

[twistedpair]

Luckily, with SpaceX hoping to drive down the cost of launches, we'll see more M2M companies like OrbComm pushing down the price of this tracking. That sad, building the constellations, and certifying the avionics, will take time.