Cringely: Wi-Fi in the Sky

Boiled Frog writes "In Cringely's latest article, he describes his plan to test a wi-fi connection between his house and his plane using two LinkSys 802.11g routers. He plans to experiment with various antennas to see which works the best."

Comments

Mesh in the Air

[bromoseltzer]

The interesting point here is that there are a lot of aircraft in the sky at any time. With a small WiFi-like box in each one, you've got a dandy mesh network. It is independent of land lines and satellites, so it is a new kind of connectivity. Whether there's any application other than aviation support isn't clear to me. The bandwidth wouldn't give you much video for the passengers, etc.

-mse

Re:Mesh in the Air

[TheSync]

At 5,000 feet, air-to-gound line of sight is 100 miles, aircraft-to-aircraft line of sight is 200 miles. Most urban areas will probably have at least one aircraft within 100 miles at any point!

As proof-of-concept, listen to VHF air frequencies, you will hear 20-30 planes over a few minutes.

I have worked space station MIR with a 5 watt handheld VHF transmitter, which is about 100 miles away.

My impression is that if all commercial airline planes carried mesh network devices that could emit a few watts, urban areas could probably have near 100% mobile digital coverage, the question being just how much bandwidth would be available, which would be a cost/benefit ratio based on how complex the devices in the planes need to be.

It also would stress the mesh routing algorithms!

Warflying...

[taubman]

Sorry Bob, someone beat you to it.

But i'd still be interested to see the results of a bi-directional test..

Re:Cringe-ly

[delcielo]

For the most part, I agree with you.

He's poo-pooing research into the matter by saying that it doesn't prove anything; and yet he's not giving any evidence that it's not true.

He does have the priviledge under Part 91 to do this in his own plane, though. The thing is, his homebuilt small plane probably has better insulation on the wiring than a mid-80's airliner. Also, he probably doesn't fly his little homebuilt on autopilot much (if it's even equipped with one) whereas an airliner spends most of its time being flown by the flight director (fancy autopilot), which is the component that we're really worried about, as it will follow a failed instrument without question, as opposed to analyzing whether or not the indications make sense. So, in the end, he won't really have proven anything regarding the RF interference issue on aircraft.

Finally, I'm not going to spend $1000 having an A&P mechanic install my $100 wifi router in my airplane. If I could just slap it in myself, that would be one thing; but with an airplane you're going to need a Form 337 approval at least, if not an STC (Supplemental Type Certificate). No big deal on the 337. It just takes time and thus money. That's money I'll be spending just help the wifi cloud when I happen to be flying? Uhh, I'll pass.

Re:Cringe-ly

[div_2n]

It isn't too hard to figure out:

1) There are in-plane phones that charge your out the ass to use them. Cell phones kind of bypass that. It isn't surprising that they don't allow cell phones in-flight.

2) I have read that cell companies say that the phones would confuse the cell network due to being able to "see" so many towers. I don't buy that as I have used my cell on top of a 250ft tower on top of a tall mountain well within the range of at least 10 cell towers. No problem as far as I could see.

3) When the terrorists took over the planes in 2001, passengers were using cell phones to make calls while the planes were going. The pilots were NOT professionals. They had enough training to steer them into buildings and that is about it. They didn't crash because of cell phones being used. Hmmmm.

You can bet that cell phones are not a danger to make planes crash. That isn't the reason they are banned. You can bet on that.