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Comment by karlgkk

2 days ago

There are reasons they don’t. This is a deceptively difficult problem

Cost is a big one (satellite data is still quite a bit more expensive than you think, especially with many stations)

And by stations, I mean aircraft. There are a TON. Current constellations probably wouldn’t even be able to handle half the current aircraft transmitting all at once. Bandwidth, in the physical sense, becomes a limiting factor

Coverage (different constellations have different coverage, which means planes would not have transmit guarantees depending on flight path). So you’d have huge gaps anyways

There have been alternative solutions posed, some of which are advancing forward. For example, GPS aware ELTs that only transmit below certain altitudes. But even that has flaws

Anyways I think we’ll see it in the next decade or two, but don’t hold your breath

There's somewhere around 15 thousand relevant planes in the air at any time.

If you sent two updates a minute over Iridium, using their 25 byte message plan, you'd be looking at a megabyte per minute for the entire planet. That's such a tiny fraction of what that single constellation can do.

Most airplanes regularly crossing oceans already do have satcom.

The cost of hardware and additional fuel consumption due to drag aren’t nothing, but the data used itself is essentially a rounding error. (Iridium for example has tiny antennas, and SBD data costs about a dollar per kilobyte, and position data is tiny.)

Of course, that’s all little help when a pilot acts adversarial; on MH370, the breakers for both satcom and transponder were likely pulled, for example.

  • Yep. Inmarsat has this data for most of the world widebody fleet, and had it for MH370... except when transmission stopped. It's not publicly shared information, because that's what the ADS-B transponder they're all equipped with is for...

> Cost is a big one (satellite data is still quite a bit more expensive than you think, especially with many stations)

That’s nonsense. Even when I’m flying right over the north pole my airline will give me unlimited in-flight internet for $20. Maybe antartica has worse reception, but cost isn’t the issue.

> Cost is a big one (satellite data is still quite a bit more expensive than you think, especially with many stations)

You get free Starlink on several airlines now, so won't that be a solved problem soon?

  • Free to passengers doesn’t mean free to the airline, and Starlink in commercial airliners is very new.

> Cost is a big one (satellite data is still quite a bit more expensive than you think, especially with many stations)

I can pay $10 to have internet for the entire flight. Reasonably low bandwidth of course, but if I can splurge $10, the airline can.