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Wireless Computing and Airplanes?
Echemus writes "The Register has an article speculating whether the fact more and more devices have WiFi/GSM facilities built in will cause Airlines to ban all computing equipment and its like from the cabin. Airlines are ultra-paranoid about cell phones, but is that paranoia justified?"
There is no way in hell I am going to check a laptop. Last year, one of the baggage handlers at LAX broke open my bag and stole some stuff out of it. American Airlines basically told me "Too bad."
" ...But has anyone actually gotten a signal while flying around in one of those big tin cans? "
Sure...at least on a Blackberry device. Usually if you're sitting by the window, and are over a LARGE city (i.e. there are LOTS of towers below you), you can get enough of a signal to send/receive messages. Darn thing's gotta be up in the window, though! This happens even at altitude...20,000 feet +.
This post on the FlyerTalk forums came directly from a Lufthansa 747 fitted with wireless internet access.
Don
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But, Marge, that little guy hasn't done anything yet. Look at him. He's going to do something and you know it's going to be good.
Slashdot - The Home of the Tortured Analogy
I've been on a plane that was trying to land and someone used their cell phone. It was a very bumpy ride. The pilot came on and said "Someone was using their cell phone on that landing, if I find out who it is, they will be reported to the police."
Newer planes use shielded wires, so are not affected by the phone's signal, however older planes or planes with corroded shielding are suseptable to cell phones causing interferance - which can cause catestrophic results (immagine if the interferance was interpereted as a signal to put the flaps full up!). Its like when your cell phone rings when you're playing music, you hear the interferance through the speakers.
So if the airlines want to upgrade their fleet to be cell-phone proof, then no, its not necessary, and they could offer wireless internet on the plane. However with pretty much all airlines now taking a major economic hit after 9/11, they arent about to spend the kind of money that would be needed to upgrade their fleet, and are more likely to just ban computers.
Unfortunately this is a rehash of old news. The fact that Mobiles, PDAs and Laptops *can* cause interference has been widely known for a long time. Anyone that has flown in the last 5 years will be familiar with the warning to turn off these devices on take off and landing. The possible Ban on laptops etc relate to the introduction of 'ultrawideband' capabilities for these devices which 'could affect a plane's electronics, including its instrument landing system and its collision avoidance systems'. Ultrawideband devices are expected to hit the stores this year, and will range from laptops to PDAs to the following military applications: Since Aircrew will not be able to tell the difference between UWB devices and regular laptops, it seems that a blanket ban may be applied. A good overview of Ultrawideband and its political consiquenses can be found here An article on Ultrawideband and its effects on aeroplanes can be found here
Airlines are not afraid of cellphones -- the FCC is.
/real/ reason they don't want all the devices running - cells, PCs, etc. - is that they want your attention during takeoff/landing and don't want you distracted. No cell phones due to the annoyance of having a loud cell talker sitting next to you jabbering away during the flight as well.
Now that makes a lot more sense than the airline fear explanation. I've flown in a few private jets and twin-engine craft and the pilots were completely comfortable with cell and PC operation. In fact, I've had no problems operating on ham frequencies as well (at hundreds to thousands more time the TX power).
I've had a few airline folks explain that the
Unfortunately, it sounds like some of the airline rent-a-cops are taking their official excuse by heart (forgetting the real reason for the policy) and are going nutso. Just like the gas station clerk who freaked when I had my cell phone active while fueling at the diesel pump (diesel doesn't work that way).
Who knows - maybe this is the beginning of the 21st century luddite revolt...
*scoove*
Here's the straight scoop. As the article says, airline people can't tell if your radio/phone/computer are transmitting any RF, let alone bad RF. Maybe a special FCC approval stamp on each device to OK it for airline use? It's not even near practical for the airlines to inspect all our gadgets before we get on the plane. And what if I *made my own gadget* (don't laugh, many HAMs still make their own radios)? I don't know nearly enough about EMI/RFI shielding and proper design techniques to insure that any gadget I make won't bring down a plane.
Yep, we're lookin at an nearly complete ban, unless the airplane manufacturers can certify their design to be EMI/RFI proof.
Well, if you're so smart, you've porbably also seen that gosh golly gee, those avionics are quite often attached to (gasp!) antennas for picking up (gasp!) radio transmissions.
Pilots are cautious for a reason- the FCC's testing of devices is not sufficient for close-range use with avionics. My father(a pilot, small single engine planes) explained it quite simply. He have no idea if a laptop will cause any of the avionics to malfunction. Maybe it doesn't...but say maybe it causes the VHF direction finder to go a little askew. After an couple hour's flight time, you find yourself way off course. Given that planes just can't pull over to gas up, getting off-course can be a major problem.
Show me independently-verified lab results that a CD player (or anything else in the cellphone or PDA category) can freak out fully functional and properly installed avionics, and I will cheerfully STFU
Oh, I see, devices "will not cause interference unless proven otherwise"? Unlike our legal system, everything that goes into a plane has to PROVE it meets FAA standards. We don't just throw shit into an airplane's equipment 'roster' and then wait for some "independent lab" to test them.
The problem is three-fold: a)you have no idea what's going to come onto the plane. There are hundreds of thousands of different electronic devices. b)you have no idea what avionics systems are in the plane c)you have no idea how the device will get used(and RF emissions from a laptop alone can vary on processor/ram activity, screen brightness, peripheral activity...) d)nobody has done even basic studies to see what general kinds of equipment cause interference.
Please help metamoderate.
In my arrogant and well informed opinion as both an electrical engineer and as an instrument rated private pilot, you need a reality check.
Modern aviation is not really so modern. Most aircraft flying today are from designs decades old. Avionics technology mostly comes from the 1950s and 1960s. It didn't take spread spectrum signalling in to account because it was mostly unknown back then.
These days, a precision instrument landing takes place with a system which depends on paired VHF and UHF channels using an AM signal to let the avionics know whether to go to the right/left or up/down. It's quite precise. It will place you at a window of airspace sometimes only 100' high +/- a few feet vertically and +/- about ten feet horizontally.
These systems cost in excess of $1M per runway to implement. It has been ossified in place around the world thanks to a bunch of international agreements based on this technology. Coordinating a new system for implementation among a world-wide forum of countries is damn near impossible. As long as this scheme works, it will be very hard to replace.
Further, aircraft electronics have to be very carefully hardened against things you would never consider in the rest of the world. For example, it has to withstand a lightning strike. Several hundred aircraft are struck by lightning every year. Thanks to this kind of certification such strikes are mostly a non-event. It also has to withstand temperature extremes that even automotive electronics might have trouble with.
Thus the certification process is long and difficult, the production quantities are relatively small, and the cost is hideous. The King KX-155 radios in my aircraft cost $2500 each to replace (with reconditioned radios) several years ago.
And then there are those who say "I'll use it and if it gives the pilot trouble, I'll just turn it off." The problem is that the only way the pilots will figure out that you're doing something to the navigation system is to figure out which navigation system is being affected. That's not an easy thing to do. Then, they have to figure out where the source of interference is coming from. Then they have to somehow explain to the cabin crew what to look for and how to turn it off. Meanwhile, the workload in the flight deck goes way up.
The only solution that will allow you the freedom to use your PDA is to put you guys in to a faraday shield. To do that you'd have to rip out the interior of the aircraft and install a metal screen around the entire cabin. Nobody in their right mind is going to do that unless new government regulations come out mandating this sort of thing.
In any case, very few aircraft cabins are deliberately designed to be isolated in this manner. If you want to know more, start here and keep reading.
I admit, the probability that something will go wrong is in fact quite small. But if things do go wrong, you and every other person on that aircraft could easily become the next big smoking crater somewhere. Are you willing to risk not only your life, but everyone else's life on board the airliner, just to get a few more minutes with your PDA?
I didn't think so.
Nearly fifty percent of all graduates come from the bottom half of the class!
I used to think that it was all imaginary, too. Then I heard about supposed incidents, and then I read an article about 69,000 logged "incidents" (as of 1996) in IEEE Spectrum.
t ur es/air1.html
http://www.spectrum.ieee.org/spectrum/sep96/fea
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A report selected from the ASRS database illustrates
this type of incident. In March 1993, a large
passenger aircraft was at cruise altitude just outside
the DallasFort Worth International Airport when the
No. 1 compass suddenly precessed 10 degrees to the
right. The first flight attendant was asked to check
whether any passengers were operating electronic
devices. She said that a passenger in seat X had just
turned on his laptop computer.
The report continues: "I asked that the passenger turn
off his laptop computer for a period of 10 minutes,
which he did. I then slaved the No. 1 compass, and it
returned to normal operation for the 10 minute period.
I then asked that the passenger turn on his computer
once again. The No. 1 compass immediately precessed 8
degrees to the right. The computer was then turned off
for a 30-minute period during which the No. 1 compass
operation was verified as normal."
The report states that it was evident to all on the
flight deck that the operation of the laptop computer
was adversely affecting the operation of the No. 1
compass. It concludes: "I believe that the operation
of all passenger-operated electronic devices should be
prohibited on airlines until the safe operation of all
of these devices can be verified."
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I flew on Korean Air once. They banned the use of portable CD players, but it was ok to use a laptop with a cd rom drive. I used my cd player anyway; you can only get drunk and pass out for so long on a 12 or 15 hour flight (Korea to NY, direct). Don't exactly remember how long it was...