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Bluetooth on an Airplane?
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?"
...Less than 32 feet away from critical in-flight avionics?
"Flyin' in just a sweet place,
Never been known to fail..."
Personally I wouldn't use it. And if I was on a plan with you, and you were using it, I'd report you. Yes the odds of it causing the aircraft to crash are small, but do you really want to take that chance?
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).
Average member of Slashdot crowd isn't fully proficient in commenting flight safety. Your local air line representative is. So why don't you pick up your phone and make a call and have your question answered in no less than 30 seconds by a professional?
Here's a 2002 article from Mobile Review that discusses that studies regarding cell phones and avionics. And they are seriously considering permitting cell phone and wifi usage in flight, as indicated by this article from December.
A wireless scanner doesnt transmit, it scans. It won't transmit unless it picks up a network to hitch on to. Unless you arent talking about a wireless network scanner, in which case i have no idea what a wireless scanner is.
If you like what I've said here, and want to read more, go to http://www.krillrblog.com
They used to say this alot for portable CD players too, though I doubt the average discman would output more RF noise than a walkman or other audio device.
Also AFAIK (dredging through my old basic electronics training and sometimes dodgy memory) RF interferance needs to be at the same or a harmonic of the broadcast frequency to generate problems.
This last part is only things I have heard, and isn't verified truth, however I have been told that the reason they don't like you using mobile phones in aircraft is less about affecting instumentation, and more about the signal "footprint" you leave on the ground as your phone tries to access the nearest phone tower. This apparantly ties up channels on multiple towers. Do take this with a grain of salt however, as I am unable to verify it as fact.
I'm on an airplane right now, over the Atlantic. Sure, THE MAN doesn't want you to turn on your devices because he thinks they will interfere with flight electronics, but you know better right?
In fact I think I'll turn on my PDA and hook it up with my powerbook via bluetooth right now, just to show them how it's done.
There, see? I'm still here! Still humming along! Plane didn't fall out of the sky!
Y'know, I don't remember the ocean being so
There is no FAA restriction on the use of any electronics in flight. It is totally up to the pilot/flight crew. A pilot flying a private 747 owned by a sports team for example can freely allow use of any electronics at any time.
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.
it is my understanding that there are two issues with cellphones and transmitters on commercial airplanes - neither of which were issues with military arcraft when I was on active duty (the 1990s).
Issue one is that airplanes move through cells too fast for most cellphones to deal with it, and that causes them to ramp up their RF signal strength and the frequency of their outbound conenction traffic in an attempt to maintain a conenction to the network. (cell phones weren't allowed on transports but our UHF, SHF, and VHF radios worked fine)
Issue two is that avionics packages are not always shielded to spec in older airframes and there is the outside chance that 'something' could go wrong. (just like the outside chance that 'something' could go wrong at the gas pump) (military airframes are emissions shielded by guys who make the tinfoil hat brigade look sane)
The technical problems are exaserbated by the social problems - namely that there isn't a lot of significant science on the validity of the fears, that there are issues of profit to be had by airlines for 'owning' connectivity onto and off of a plane in flight, and that the technology landscape is a too fluid for the legislative response to be valid. Add to this the blanket of "security" as a catch all excuse for anything feasable but hard, and you begin to get a real picture of the situation that results in the "no transmitters" rule.
The bottom line is that, while there may be no compelling technical reason to ban transmitters (my opinion) no one wants to be responsible for making the call and then have an NTSB report come back naming cell phones as the cause of a airline crash.
Until that changes, it is illegal, just like replicating digital instances of copyrighted material, carrying a disposable lighter or wooden matches through security, making jokes about something being "da bomb", asking to see the regulations on presenting ID at the gate, or telling your less geeky pal how to defeat the ROT-13 encryption on his e-book.
Turn off your wifi and bluetooth before you get on the plane.
As I said earlier, I used to work on the systems that are in use today. I am an industry expert. Yes the odds are against you causing a problem.
But it CAN happen.
The worst place for it to happen is when you're in the weather, flying on instruments, and the plane already has some kind of problem. Then you're going to crash and die. Or burn to death in the wreckage.
You can quote your own ancedotal evidence, but again, I used to test those systems for a living. I'd rather not put a million to one chance against the lives of a plane full of people, or myself.
It has nothing to do with "interference" with the electronic systems on the plane. Rather it's a social engineering trick. You see, when you're at 10,000 feet all the mobiles are out of reception range. So any calls or SMS are temporarily diverted to voicemail or messagebank. When the plane lands, suddenly every phone is in reception and all the stored voicemails and SMS flood through to every mobile on the plane. Simultaneously every mobile starts that stupid BEEP BEEP BEEP noise that lets you know about your stored messages. Imagine 700 mobiles all going BEEP BEEP BEEP in unison! It's enough to drive you mad. The flight attendants got pissed off at the noise and cleverly invented this cock and bull story about "interference". Now the mobiles are turned off until you reach the baggage claim area where everybody turns on their mobile phones and annoys the baggage claim attendants instead. You see, the flight attendants have this secret war going on with the hated baggage claim attendants; you and your mobile phones are merely pawns in their devious mind games. Muahahaha.
Tell your dad to check NASA's Aviation Safety Reporting System database. He should be familiar with it. There are many, many, reports of passenger electronics devices causing problems with aircraft systems.
Mea navis aericumbens anguillis abundat
...take this into consideration. :-)
IRC: Grounded0 @ IRCnet. "I was lucky get into computers when it was very young & idealistic industry" -Steve Jobs
I don't know about you, but I was on a flight out of Singapore once...
,blah, casual pilot chatter). Turn off all your cellphones for the duration of the flight, please."
Casual Pilot: "Good evening everyone, we're ready to taxi, estimated flight time to Sydney is 8 hours, (blah
Plane begins to taxi.
Plane abruptly stops taxiing.
Grumpy Pilot: "Whoever's using their cellphone, please turn it *off*. Crew, search the cabin."
After a pause of a few minutes, Plane begins taxiing again.
So, hell, maybe they've got a few blinkenlights that blink when someone's got the phone on. As for bluetooth, yes, the power is miniscule. 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.
So, I think they (and I!) would rather just leave the unknown variables out of the whole flying equation as much as possible, thanks very much.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.
Dear /. readers.
I'm an FAA certificated private pilot of several years. I work in the aviation industry and have had some interesting experiences with this exact issue.
I do not know that, or pretend to know that operating any RF devices will "crash" an aircraft.
I DO know that even leaving a cell phone on during flight can interfere with avionics and communications. This is from real experience - and it was *very* distracting.
Here's the story: Flying closed traffic touch & goes at Oakland International Airport, my instructor (CFII) and I were both hearing a loud static noise at two places in the pattern. This was pretty darn distracting to say the least. Here we are, doing proficiency drills (landings / pattern / emergency landing without power, etc) and there's a darn buzzer in our ear shortly after takeoff and at midfield. What was it? I had left my cellphone on accidentally and buried deep in my flight bag. It was soo annoying that I asked my instructor to fly the plane while I akwardly tried to twist around the seat of the C172 and find the cell, and only was able to after several painful moments - but it was worth it for how annoying the buzzing was.
Now, this was a Day VFR (visual flight rules) flight under nearly ideal conditions. Most major aviation accidents that occur have some level of human factors that play into the incident. Further, the NTSB establishes a "chain of events" that leads up to the accident - any one of which being broken would likely have prevented the accident.
Let me ask you this. You are cruising at night in IFR conditions (in the clouds, no horizon) 30,000 feet in a commercial aircraft and the pilot loses his artificial horizon. Immediately, the pilot informs the copilot and the copilot starts flying the aircraft on his 'good' instrument. You land safely. This exact scenario was one of the more recent fatal airliner accidents in Asia, except that the pilot was distracted and did not properly give control to the copilot.
Do you want the pilot of your aircraft to be distracted by frequent buzzing in his/her headset? Aircraft these days have the capability of flying and landing themselves. Pilots are largely there for two reasons (IMHO). One of these is to re-assure the public. The other, perhaps more valid, is to deal with emergency situations. Please - don't mess with them, once the autopilot is disabled/off, they're your only chance.
A quick stroll through the ASRS database, searching on "RF Interference" or "EMI"
Report # 541518
DEPARTING SFO WE WERE ADVISED THAT ATC WAS NOT RECEIVING OUR TRANSPONDER. THE ATC FAIL LIGHT WAS ON AS WELL AS NUMEROUS TCASII FAULT MESSAGES. WE SWITCHED TO TRANSPONDER NO 2 AS PER THE OPERATING MANUAL AND ATC WAS ABLE TO RECEIVE IT. THE AIRPLANE HAD ONLY ONE MODE S TRANSPONDER SO WE HAD NO TCASII AT THIS POINT. THE FLT CONTINUED NORMALLY FOR ANOTHER HR OR SO WITH NO CHANGE IN THE STATUS OF THE NUMBER 1 TRANSPONDER AND TCASII. IT WAS AT THIS POINT THAT I DISCOVERED THAT I HAD INADVERTENTLY LEFT MY PCS PHONE ON. AND THAT IT WAS IN SEARCH MODE. I TURNED IT OFF. IMMEDIATELY, ATC NO 1 AND TCAS WERE RESTORED TO FULL FUNCTIONALITY. NO FURTHER ANOMALIES WERE OBSERVED DURING THE FLT.
Report # 536654
NAV INTERFERENCE. OVER CHT, CLRED '10 DEGS R INTERCEPT LOC RWY 31L PLAN CIRCLE RWY 22L.' UPON TUNING LOC FREQ AND SETTING COURSE, IT APPEARED WE WERE ON THE LOC, ALTHOUGH VISUALLY WE APPEARED S OF COURSE. ATC ASKED IF WE HAD INTERCEPTED AND SAID WE WERE S OF COURSE. THE CDI THEN SWUNG FULL SCALE TO THE OTHER SIDE INDICATING WE WERE N OF COURSE. I TURNED TO CTR THE CDI AND WE SWITCHED TO TWR. MY CDI SWUNG R INDICATING WE WERE S OF COURSE. I NOTICED THE FO'S CDI WAS SWINGING THE SAME DIRECTION AS MINE, BUT MOVING ABOUT HALF AS FAR. WHEN WE SAW THE RWY, WE WERE N OF COURSE WITH CDI'S INDICATING WE WERE S OF COURSE. WE WERE HIGH AND WELL N OF COURSE WHEN TWR ASKED IF WE COULD GET DOWN FROM THERE. WE ASKED TO BE TURNED OUT TO RE-ENTER THE PATTERN. UPON TURNING OUTBOUND WE MADE A PA ASKING PEOPLE TO PLEASE MAKE SURE THEIR CELL PHONES AND OTHER EQUIP WERE TURNED OFF. THE CDI'S IMMEDIATELY BECAME STEADY AND WE COMPLETED A NORMAL ILS RWY 31C CIRCLE RWY 22L WITH NORMAL INDICATIONS AND THE FLT ATTENDANTS RPTED THAT A WOMAN IN THE FORWARD LOUNGE WAS TALKING ON HER CELL PHONE. AS SOON AS SHE TURNED HER PHONE OFF, OUR CDI INDICATED NORMALLY.
Report # 283948
CLBING THROUGH 13000 FT MSL, RADIO ALTIMETER INDICATED 900 FT. GPWS SOUNDED 'TOO LOW TERRAIN.' THIS WARNING CONTINUED FOR SEVERAL MINS. HAD FLT ATTENDANT CHK CABIN FOR ELECTRONIC DEVICES. PAX WAS FOUND WITH CELLULAR PHONE 'ON' BUT NOT IN USE. PAX SHUT OFF CELLULAR PHONE AND PROB STOPPED. NO FURTHER PROBS DURING REST OF FLT OR RETURN LEG (ORD-LGA-ORD).
It wasn't so long ago that the airlines banned PDA-cellphone combinations such as the Treo. Now, many airlines including AA, Southwest and JetBlue allow you to use your Treo if you can show the flight attendant that the wireless feature is turned off (see, e.g., the back pages of American Way magazine). All it would take is one ***hole to be found interfering, say, with the intracabin communications system used by the Federal Air Marshals to have the policy revoked, and then I wouldn't be able to read ebooks or AvantGo on airplanes anymore. Thanks a lot.
Have you ever played with those science exhibits where two parabolic reflectors are seperated by a large distance in a room? You talk towards one, and someone at the other reflector can hear you clearly while others between you cannot.
Have you ever driven a car that, at a certain speed or on a certian road, the car got *very* loud, and all you had to do was speed up or slow down to dampen the noise?
The first example has to do with reflection. The second has to do with resonance.
In a flying tin can you cannot possibly know where the reflections and resonance will occur. You do not know what equipment may or may not be affected by your transmissions.
While holding your cell phone next to an avionics box may have no effect, sitting in seat J23 with the cellphone in your pocket as it broadcasts at maximum power (because, see, you're in a tin can) may be just the spot to form a nice reflection which, coupled with a resonance, would put a very strong signal right at the wrong spot of an important piece of equipment.
Your blue tooth has the same problem, though the frequencies are difference, and the power *should* be less. This doesn't actually make it any less dangerous, however.
The plane you are riding in is likely very old. The equipment can easily be more than 20 years old, and if the equipment itself isn't, the design is.
The long and short of it is: Planes are a bad place to use equipment that intentionally radiates (ie, transmits). They aren't so great for devices that unintentionaly radiate either.
While "testing" does take place there is no way to ensure that everything will operate properly in real conditions - only a complete design analysis could come close to providing that information.
-Adam
I doesn't really matter whether its a risk or not - the fact remains that failure to follow the directions of the airline crew is a federal offence.
"When I grow up, I want to be a weirdo"
What a bunch of crap. I mean serieously. I don't care if you are an electrical engineer with 20+ years of pilots experience, or a super tester avionics tester at NASA, because obviously you don't know shit. (with 'you' I mean everybody that thinks it could interfere or the like).
/. in the first place : ).
More informed slashdot readers should remember these articles.
Yes Wifi on airplanes is a reality allready, and experiments with bluetooth and GSM are on the way aswell. (Actually that article was 'pre' lufthansa's wireless service).
So seriously, lay of the crack, because obiviously it doens't do you any good.
P.S. Whoever felt offended by this post should have read