Saturday, April 14, 2007

Cell Phones, Mythbusters, and Selective Perception

In a recent Usenet discussion, the question of whether cell phones on airplanes were actually a problem came up. Several people mentioned a Mythbusters episode on the subject. What was interesting was that some of them claimed the episode showed that cell phones were not a problem, others that it showed that some cell phones were a problem. Googling around, I found the same inconsistency in webbed comments by various people citing the program.

The situation became clearer when I found a fairly detailed webbed description of the program. The people at Mythbusters were unable to get permission to actually test a cell phone in an airplane in the air--cell phones being forbidden to operate in airplanes in the air. Instead, they did two experiments:

1: A signal generator to simulate a cell phone, a navigation gauge, and various other equipment were placed inside a faraday cage (to eliminate external interference). They found that signals in the 800-900 MHz range affected the navigation gauge.

2. An actual airplane was borrowed and tested on the ground. No signal they tested had any effect on its electronic equipment. They concluded that the difference was that the electronic equipment in a real airplane is shielded, whereas in the first experiment the signal generator was more or less next to the unshielded navigation gauge.

So it is true both that they found that a cell phone had no effect on an airplane's electronics and that they found that some cell phone signals could affect the kind of electronic equipment in an airplane. I suspect that listeners selectively remembered the part of that that fit their existing beliefs and prejudices.

I also found a discussion of the issue of cell phones on airplanes, from the sceptical side of the argument, in a Computerworld article. The author thinks that both the regulators and the airlines are in favor of the ban for reasons unrelated to safety risks from interference. The article provided a link to an FCC press release which amounts to "we decided to stop our investigation into whether cell phones should be banned on airplanes because we couldn't find enough evidence to tell," which strikes me as some evidence in favor of the sceptics' view of the situation.

11 comments:

Chris Bogart said...

I took a cross-country bus ride in Turkey, and we were told not to use cell phones because they could interfere with the brakes. Seemed rather unlikely to me; I figured it was a fairy tale to prevent people from annoying other passengers with their calls.

Ross Levatter, MD said...

I believe it's commonplace (and reported so) that journalists on planes with political candidates routinely use cell phones to phone in stories on deadline. They even joke about how the law doesn't apply on planes for politicians. I assume they're talking about the laws of physics, as we've always known the other laws don't apply...

Mike Huben said...

I'm sure that this is a huge conspiracy, and the burgeoning cellphone/wireless communications industry is helpless against the failing airline industry. It would be impossible to even suggest standards for cellphones and aviation equipment that would make them compatable.

It's all part of the same conspiracy that prohibits our using cellphones during movies and during standardized tests.

Along those lines, throughout the third world, pets and livestock routinely travel in passenger compartments. Perhaps we should worry more about this first world infringement on our liberties.

(***sarcasm***)

Anonymous said...

The Economist had a very fun piece on what an in-flight announcement would sound like if the flight attendant actually told the truth, and if memory serves me well, there was a part dedicated to cell phones. Unfortunately, it's now gone behind a pay wall.

Anonymous said...

I do a lot of traveling in my line of work. In the past five years, I have been on hundreds of flights all over the world and I have never turned off my cell phone. In all this time, my phone caused the plane to crash only five times and, luckily, I only died twice. Therefore, I think the safety risk has been greatly exaggerated.

Gary McGath said...

The Mythbusters test is irrelevant. What currently concerns the FCC isn't interference with operation of the plane's equipment, but the effect of a phone which is high up, therefore in line of sight with a lot of towers, and moving fast. Supposedly it can have a heavy impact on traffic.

This is discussed here.

Anonymous said...

I took flying lessons in a C172, cute little plane, just a few years older than a Pinto. i can tell you guys 100% that cellphones do interfere with the radio's on those planes. I could tell when I forgot to turn my phone off or put it in the back seat because several times during the flight buzzing would come over the headsets. If I were a commercial pilot with 60 phones in the back buzzing my headsets, I'd have a headache and possible trouble making out the weaker calls.

`Koa said...

Interesting, considering that cellular telephones are not the huge transmitters they used to be.

Hooray for selective perception!

Andrew said...

I would estimate that a typical commercial flight has at least ten cell phones on throughout the duration of the flight. Many people do not know how to shut off their phones, and others forget to do so.

I would probably go crazy if i had to sit near people talking on cell phones through a whole flight.

jimbino said...

I have a AM/FM-shortwave radio that I usually keep in my carry-on baggage. Like almost all radios, it has a provision to turn on the radio in response to an alarm setting. I have often retrieved my overhead baggage at the end of a flight to find the radio happily playing away.

Now, the prohibition of turning on radios or similar devices is a joke or it isn't. If it isn't, the airlines are mighty lax in protecting the public! I assume it's another airline scam to sell us cellphone service or something else, just as is the ban on consuming your own liquor onboard.

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