Bluetooth on an Airplane? 145
bblazer asks: "Since I travel quite a lot, I am very familiar with the warnings about cell phone use on an airplane (could be bunk, but I still respect it and those around me). But what about using Bluetooth? I just got off an Alaska Airlines flight where the flight attendant said that we were not permitted to use any device that sends or receives a radio signal. I often use the bluetooth features of my PowerBook and Treo while onboard a plane (you can have the Treo on without having the cell phone on), or I set up a mini-network with others I may be traveling with. Could Bluetooth cause any problems, or is this something I need not worry about?"
Yes it could cause problems. (Score:2, Insightful)
Anything that transmits has a chance of interferring with the signals the plane's navigation equipment receive. As the quality of a lot of consumer electronics isn't very high, the possibility that some unit may be broadcasting some horrendous noise on an off frequency is realistic.
Last of all, with these new fly by wire aircraft (and one company in particular has had major mishaps because thier code stinks), do you really want to do anything that might introduce a spurious signal into a system that can't deal with it?
I'd sure rather not.
(PS I used to test aircraft systems for a major aerospace company, my observations here are based on real life work experiences).
Wrong place for such question (Score:4, Insightful)
Re:Phones and other devices.... (Score:2, Insightful)
No FAA restriction of any kind... (Score:4, Insightful)
There are specific restrictions imposed by the FCC depending on the band in use, such as cell phones, and that is on it's way out.
Unless the FCC has applied restrictions to the band - you can freely use whatever you want subject to the requirements of the flight crew.
Now, that's not to say any pilot is going to approve - in the world of lawyers, it's far easier to say no than to take any risk, even if it's practically nonexistent. Think about it - the first accident that occurs after a pilot allows it - it's going to get blamed, even it it has nothing to do with the real reason for the event.
Re:Yes it could cause problems. (Score:1, Insightful)
the parent poster is probably fine on a Boeing or (shudder) Tupolev bird, but airbuses are dangerous...
Re:No FAA restriction of any kind... (Score:3, Insightful)
Re:Yes it could cause problems. (Score:5, Insightful)
First, the reason cell phones are banned was they cell sites couldn't handle the handoffs of cell phones in air. The wireless communications companies asked the airlines to stop in flight calls, and offered and created companies just for in fight service.
2nd. Fly by wire isn't, fly by RF, there are actual wires, and these wires wont pick up RF from a device as you say. If you're simple phone could put it out of service, any plane flying over a guys house with a HAM radio would crash it. Planes don't crash from RF like that.
And you say you worked for the industry, well guess what, so do I.
BTW, did you want a cookie for reporting the big bad man to the air stewardess (HA, Fuck Political Correctness)...
Re:Wrong place for such question (Score:3, Insightful)
Most flight safty rep's will just read of a list of things they dont allow. They dont or have not tested RF in planes. Manufacturers do.
So, since a large group of engineers who do read Slashdot and design electronics for RF gear, or work in the RF industry might know a thing or 2.
Why believe everything you read or someone tells you. Question.
Youre an adult, "Because I told you" is not a good enough answer. Facts are.
Re:Maybe you've just been lucky... (Score:4, Insightful)
Planes don't crash when they fly in areas that have radio towers, they don't crash when flying under satellites, they don't crash when people "accidentally" leave their cellphone one. But, of course, in the lab, when you turn on a cellphone right next to a radio receiver, you get little blips, oscillations, or otherwise see some minor effects. Yet it's absolutely clear that these effects aren't important in the real world. Is it because the radio sources are located tens of meters from the equipment? Is it because the effects are minimal (the device doesn't need the tolerances that the variations on your scope shows)? Is it because you cherry pick your results (well, if the system is hit by lightning and there are four cellphones equadistantly distributed around the plane at 25m, and they ring in order, the plane will think its headed backwards for 300ms)?
When people believe a theory that contradicts reality, we call it superstition.
You can quote your own ancedotal evidence
And you quote yours. Who wins in this discussion? How about the person whose claims actually match reality?
Now, if you have examples of planes being downed by a cellphone, I'm all ears. Let's hear some facts that turn your superstition into reality, if you're so convinced.
Re:Well. (Score:1, Insightful)
Grumpy Pilot: "Whoever's using their cellphone, please turn it *off*. Crew, search the cabin."
I'm gonna go ahead and say that, with no formal knowledge of electronics, and years of people telling him that cell phones do bad things, he attributed whatever bad thing was happening to the cell phone without any particular evidence. I could be wrong, but I dare you to prove it.
But as a pilot, you'd be pissed off if the plane you're flying lost some crucial function, because of eg. an overload of some very sensitive preamp that happens to be in the roof just above some passenger using bluetooth.
As a pilot, I'd be really annoyed that a professional engineer decided to use a really sensitive op-amp in my plane, and to leave it unshielded. Being angry at the passenger is like being mad at the power company when your UPS exlodes during a brownout.
A kick in the face to other Treo users (Score:3, Insightful)
Its not just a good idea, its the law. (Score:3, Insightful)
Re:Yes it could cause problems. (Score:2, Insightful)
When you are in an areoplane the signal from your mobile will travel up towards 50 miles (+/- depending on altitude) and you will connect with hundreds of GSM accesspoints. This is where the problems come in. The GSM backbone cannot, since the signal is traveling so fast, figure out which accesspoint is to be the master, and you will in a sence overload the system.
The bluetooth signal is not powerfull enough to create disturbances in electronics that are more than about 1 foot away from the broadcast antenna, even though it sends at 2.41 ghz... think about your laptop - if bluetooth could interrupt signals don't you think that your laptop would stop working as soon as you turn on bluetooth !!!
I thought that everybody knew the facts about why mobiles etc. are prohibited on areoplanes... Laptops, and other electronics of that kind, are not allowed to be on/used during takeoff and landing, because of your safety, not the plane.