Turn OFF and Stow All Electronic Devises: WHY

Old Nov 5, 07, 11:29 am
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Turn OFF and Stow All Electronic Devises: WHY

I c &p'd this from a member only NW forum:

Please Shut Off All Portable Electronic Devices

“I can understand cell phones, pagers, or anything that transmits or even receives signals, but why exactly do I have to turn off my iPod, CD player, or anything with an on/off switch when we take off and land? Does it really interfere with the aircraft…and if so, how?”

The FAA regulation that covers this topic is Advisory Circular 91.21-1B. Agency spokesman Les Dorr says that “while an Advisory Circular is not mandatory, in practice all airlines and other operators adhere to its provisions. Airlines generally consider the ‘prohibited’ period to begin when the cabin door closes for pushback.” One big reason is lawyers. The FAA’s regulation makes the airlines responsible for governing the use of portable electronic devices on their airplanes, ensuring that carriers err on the side of non-litigious caution.

The ban on cellular phones is fairly easy to understand. Not only do they transmit signals, they might interfere with cellular signals on the ground. For that reason, it isn’t just the FAA that limits their use on airplanes. The Federal Communications Commission has recently supported the FAA’s decision to keep cell phones turned off during the entire flight, not just during takeoff and landing.

But what about laptops, iPods, and other devices that don’t have to receive signals to work? The reason these devices are banned is that they emit radio waves. All wireless devices do, and the navigation and flight control computers on airplanes are designed to sense even very weak signals coming from far away. Radio waves with just the right power and frequency can in theory introduce errors in computing equipment.

Case in point: In 1995, a passenger’s laptop computer was reported to cause the autopilot on a 737 to disconnect. Boeing bought the computer from the passenger and sent it to the lab for testing. Scans showed the laptop emitting frequency-range levels exceeding the company’s pre-set limits for equipment on airplanes.

“Sometimes [interference] appears, usually it does not,” says Victoria Day, a spokesperson for the Air Transport Association, a trade group for U.S. airlines. “It may present pilots with an annoyance, or it may threaten safe operation of the airplane. During takeoff and landing when the airplane is closer to the ground, there is no room for error, and airlines take every precaution to ensure that no interference occurs.”

Advisory Circular 91.21-1B:
http://www.airweb.faa.gov/Regulatory...2091.21-1B.pdf
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Old Nov 5, 07, 11:32 am
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Because if you're listening to your iPod, you can't hear the instructions from the crew.
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Old Nov 5, 07, 11:37 am
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Originally Posted by MarcoPolosFootprints View Post
I c &p'd this from a member only NW forum:

Please Shut Off All Portable Electronic Devices

“I can understand cell phones, pagers, or anything that transmits or even receives signals, but why exactly do I have to turn off my iPod, CD player, or anything with an on/off switch when we take off and land? Does it really interfere with the aircraft…and if so, how?”

The FAA regulation that covers this topic is Advisory Circular 91.21-1B. Agency spokesman Les Dorr says that “while an Advisory Circular is not mandatory, in practice all airlines and other operators adhere to its provisions. Airlines generally consider the ‘prohibited’ period to begin when the cabin door closes for pushback.” One big reason is lawyers. The FAA’s regulation makes the airlines responsible for governing the use of portable electronic devices on their airplanes, ensuring that carriers err on the side of non-litigious caution.

The ban on cellular phones is fairly easy to understand. Not only do they transmit signals, they might interfere with cellular signals on the ground. For that reason, it isn’t just the FAA that limits their use on airplanes. The Federal Communications Commission has recently supported the FAA’s decision to keep cell phones turned off during the entire flight, not just during takeoff and landing.

But what about laptops, iPods, and other devices that don’t have to receive signals to work? The reason these devices are banned is that they emit radio waves. All wireless devices do, and the navigation and flight control computers on airplanes are designed to sense even very weak signals coming from far away. Radio waves with just the right power and frequency can in theory introduce errors in computing equipment.

Case in point: In 1995, a passenger’s laptop computer was reported to cause the autopilot on a 737 to disconnect. Boeing bought the computer from the passenger and sent it to the lab for testing. Scans showed the laptop emitting frequency-range levels exceeding the company’s pre-set limits for equipment on airplanes.

“Sometimes [interference] appears, usually it does not,” says Victoria Day, a spokesperson for the Air Transport Association, a trade group for U.S. airlines. “It may present pilots with an annoyance, or it may threaten safe operation of the airplane. During takeoff and landing when the airplane is closer to the ground, there is no room for error, and airlines take every precaution to ensure that no interference occurs.”

Advisory Circular 91.21-1B:
http://www.airweb.faa.gov/Regulatory...2091.21-1B.pdf
I believe that this rule is for a different reason than the cell phone. During take-off and landing it is much more likely for an aircraft to hit bumpy air and that can turn a cd player, laptop, or dvd player into a deadly projectile. I hit clear air turbulance over the pacific a few years back and if it was not held down, it was in the air. Nobody hurt but I woke up real quick and can see how having relatively heavy, small objects out and unsecured could be a saftey issue.
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Old Nov 5, 07, 1:08 pm
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Old Nov 5, 07, 2:10 pm
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I've been told that it's not an interference or electrical problem, but that takeoff and landing are the points during a flight where the most problems may arise. If the flight crew needs to give instructions for evacuation, and people need to move FAST then it's important that everyone hears it. It's similar to the reason why seatbacks must be upright and tray tables need to be stowed.
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Old Nov 5, 07, 2:14 pm
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There are numerous reasons not the least of which is the flight attendants don't have to the time to babysit each person and inspect each and every device they use and make snap judgements as to whether or not said device is endangering the life of the crew, staff and passengers. Takeoff and landing are the two most dangerous times in flight and being certain that no devices are going to cause a problem with the flight electronics if very important. Allowing some devices to be operated opens the door to people using the wrong devices.

Flying is about getting you first and foremost from point A to point B safely. The next time you're flying and feel this is a hassle, take a moment to recollect that you're flying on a large tin can filled with highly explosive fuel at 500MPH. Eliminating possible points of failure in the process means that yes, you have to shut off your iPod.
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Old Nov 5, 07, 3:41 pm
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Please continue to follow this thread in the TS/S Forum
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Old Nov 5, 07, 7:19 pm
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Originally Posted by thegeneral View Post
Flying is about getting you first and foremost from point A to point B safely. The next time you're flying and feel this is a hassle, take a moment to recollect that you're flying on a large tin can filled with highly explosive fuel at 500MPH. Eliminating possible points of failure in the process means that yes, you have to shut off your iPod.
So based on this overriding focus on safety, and the history of 9/11, clearly we need to take action to make the flight safe. I would suggest shackling all passengers to their seats!

Sorry, but if the iPod can generate enough RF to make the plane crash then a terrorist should be able to buy a microwave from Sears and bring down any plane he wants.
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Old Nov 5, 07, 10:55 pm
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Originally Posted by JakiChan View Post
So based on this overriding focus on safety, and the history of 9/11, clearly we need to take action to make the flight safe. I would suggest shackling all passengers to their seats!

Sorry, but if the iPod can generate enough RF to make the plane crash then a terrorist should be able to buy a microwave from Sears and bring down any plane he wants.
So they explicitly allow the iPod shuffle and nano due to their sizes. Then you have pax who says his video iPod isn't much larger, can be secured beneath the leg or tucked into the seatbelt during takeoff, so it should be allowed too. They allow that. A month later, another pax demands that his iPhone be allowed because, with the phone turned off after all, it's just an iPod. So they allow it. Then some other pax complain that their ultra-mobile PC's (UMPC's) should be allowed also because they're not really much larger than the iPhone and they too should be allowed to listen to music. So they allow it.

But wait! The small form factor laptops aren't much larger than the UMPCs. And the standard sized notebooks aren't much larger than those.

Now, I think we are all behind the idea that me listening to Girls Just Wanna Have Fun on my iPod nano at liftoff won't cause my plane to crash to the earth in a fireball. But once you've opened the door to some devices and not others, it's going to be completely arbitrary when they finally draw that line in the sand.

It's easiest for all parties involved to go with the "NO electronic devices" allowed at takeoff and landing. If someone can't last 10 minutes without music at each end of a flight, they have bigger problems than the current FAA regulations.

PS.
The terrorist would NEVER be able to get that microwave through the TSA checkpoint.
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Old Nov 6, 07, 6:01 am
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Originally Posted by oneant View Post
If someone can't last 10 minutes without music at each end of a flight, they have bigger problems than the current FAA regulations.
Ten minutes? Perhaps during de facto "irregular ops". I cannot recall the last time I landed 10 minutes after prep to land. Add to that take off and landing delays and I wonder in what idealized world 10 minutes of prep for takeoff and landing exists.

NB: Emphasis mine
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Old Nov 6, 07, 9:51 am
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Originally Posted by MarcPHL View Post
Ten minutes? Perhaps during de facto "irregular ops". I cannot recall the last time I landed 10 minutes after prep to land. NB: Emphasis mine
ok, then more than 10 minutes. if you cannot do without for whatever the amount of minutes will be. emphasis mine
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Old Nov 6, 07, 11:27 am
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Originally Posted by MarcoPolosFootprints View Post
Case in point: In 1995, a passenger’s laptop computer was reported to cause the autopilot on a 737 to disconnect. Boeing bought the computer from the passenger and sent it to the lab for testing. Scans showed the laptop emitting frequency-range levels exceeding the company’s pre-set limits for equipment on airplanes.
It couldn't be replicated and wasn't proven to be the cause of the disconnect.
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Old Nov 6, 07, 2:13 pm
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Originally Posted by oneant View Post
The terrorist would NEVER be able to get that microwave through the TSA checkpoint.
If the planes are THAT sensitive to RF he wouldn't need to. They could just be somewhere near the airport and take them down with microwave emitters.

Originally Posted by LHstatus
if you cannot do without for whatever the amount of minutes will be. emphasis mine
So you'd be fine with them banning ALL electronics, "in the name of safety" for the ENTIRE duration of the flight? You just want to sit there with your Sky Mall catalog?
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Old Nov 6, 07, 2:35 pm
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Originally Posted by JakiChan View Post
If the planes are THAT sensitive to RF he wouldn't need to. They could just be somewhere near the airport and take them down with microwave emitters.
That was my attempt at humor.
Originally Posted by JakiChan View Post
So you'd be fine with them banning ALL electronics, "in the name of safety" for the ENTIRE duration of the flight? You just want to sit there with your Sky Mall catalog?
How are you going from banning electronic devices at takeoff and landing to banning them for the ENTIRE flight? What is your basis for this?

I'm fine with my SkyMall catalogue and my Famous Jewish Sports Legends pamphlet for the small durations at the beginning and end of the flight.
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Old Nov 6, 07, 2:39 pm
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Originally Posted by JakiChan View Post
If the planes are THAT sensitive to RF he wouldn't need to. They could just be somewhere near the airport and take them down with microwave emitters.



So you'd be fine with them banning ALL electronics, "in the name of safety" for the ENTIRE duration of the flight? You just want to sit there with your Sky Mall catalog?
What about every electronic watch on every PAX on board?
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