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There's a big difference in power levels between wifi (that only has to go a few hundred feet to the on-plane transceiver) and cell phone radio (that has to go
by bdonlan 15y ago
There's a big difference in power levels between wifi (that only has to go a few hundred feet to the on-plane transceiver) and cell phone radio (that has to go possibly several miles to a ground tower). Additionally, GSM has a transmission pattern that can cause noise in radio receivers and other audio devices - just try holding an active GSM phone up against a poorly shielded speaker sometime!
- pyre 15y agoGood to know that avionics electronics have the same build-quality as poorly-shielded speakers!
- brk 15y agoI know all this. I also know that people will forget to turn their phones off, will have phones and laptops and all manner of devices in checked luggage that are possibly left on, and that these signals are all around the plane anyway. If there were any credible threat from leaving your phone on, or having it actively transmitting, then ALL phones would be outright banned from the plane. Otherwise, a group of terrorists could take down a plane simply by passively not turning their phones off? When you look at all of the other TSA security theater bullshit, it's a safe conclusion (IMO) that the RF from your phone will not interfere with the operation of the plane, based on the simple fact that they are not banned in the first place. Not to mention, I think that if this were even a moderate concern it would be easy to equip the flight attendants with an RF monitoring device they could walk down the aisle with and detect close-proximity transmitters from cell phones. On modern flights where coach seats have been spaced at the minimum allowable level and people are forced to bring everything as carry on to avoid bagge fees you see far more safety threats from under-seat luggage sticking out into the seating aisle, potentially inhibiting safe exit of the plane in an actual emergency.
- gnaffle 15y agoLithium Ion batteries are allowed on planes as well. Is this conclusive proof that they can't damage the plane if they catch on fire? All decisions are trade-offs, banning laptops and cellphones today would probably bankrupt the airlines since nobody would fly. Likewise, non-critical computer systems in an airplane have less stringent certification standards than critical systems (it's OK for the electronic flight bag laptop to occasionally crash if you keep a stack of paper charts in the cockpit). It's not like a plane is likely to just go down because of interference, but instruments acting will certainly increase the workload of pilots, making an accident more likely. Likewise, people shining lasers at airplanes tell themselves that this is OK, surely the pilots can deal with a little light disturbing their night vision? They don't appreciate that the pilots already have a high workload during landing. The wikipedia article (http://en.wikipedia.org/wiki/Mobile_phones_on_aircraft http://en.wikipedia.org/wiki/Mobile_phones_on_aircraft) has a link to a NASA study of interference events showing that they can in fact happen (although not often). Of course, you can still claim that these pilots are making stuff up or that this is another NASA conspiracy, but it's actually possible to read up on the subject instead of just offering wild theories and speculations based on your own opinion and wishes.
- lubujackson 15y agoAgain, the issue is that ALL electronics must be turned off, signal or not.
- X-Istence 15y agoWifi is limited to 1 watt of power max. Cell phones can transmit at up to 2.5 watt.
- sjwright 15y agoAwesome. So I'll turn on my laptop, mobile phone AND my iPad. That's three watts.