Tests Cast Doubt on F.A.A. Restrictions on Kindle and iPad - Nick Bilton via NYTimes.com

Nick Bilton does some real science, and proves that the FAA’s restrictions on electronics during take-off and landing is not based on actual emissions from the devices. It’s all security theater.

The Federal Aviation Administration has its reasons for preventing passengers from reading from their Kindles and iPads during takeoff and landing. But they just don’t add up.

Since I wrote a column last month asking why these rules exist, I’ve spoken with the F.A.A., American Airlines, Boeing and several others trying to find answers. Each has given me a radically different rationale that contradicts the others. The F.A.A. admits that its reasons have nothing to do with the undivided attention of passengers or the fear of Kindles flying out of passengers’ hands in case there is turbulence. That leaves us with the danger of electrical emissions.

For answers, I headed down to EMT Labs, an independent testing facility in Mountain View, Calif., that screens electrical emissions of gadgets that need to pass health, safety and interference standards.

Before I share the results of the tests EMT ran, let me explain what this means. Every electronic device throws off electrical emissions. This is the slight hum of energy that emanates from a device when in use. Labs like EMT test electronics of all sizes to ensure that they meet government standards and will not interfere with other electronics when in use.

Gadgets are tested by monitoring the number of volts per meter coming off a device. The F.A.A. requires that before a plane can be approved as safe, it must be able to withstand up to 100 volts per meter of electrical interference.

When EMT Labs put an Amazon Kindle through a number of tests, the company consistently found that this e-reader emitted less than 30 microvolts per meter when in use. That’s only 0.00003 of a volt.

“The power coming off a Kindle is completely minuscule and can’t do anything to interfere with a plane,” said Jay Gandhi, chief executive of EMT Labs, after going over the results of the test. “It’s so low that it just isn’t sending out any real interference.”

But one Kindle isn’t sending out a lot of electrical emissions. But surely a plane’s cabin with dozens or even hundreds will? That’s what both the F.A.A. and American Airlines asserted when I asked why pilots in the cockpit could use iPads, but the people back in coach could not. Yet that’s not right either.

“Electromagnetic energy doesn’t add up like that. Five Kindles will not put off five times the energy that one Kindle would,” explained Kevin Bothmann, EMT Labs testing manager. “If it added up like that, people wouldn’t be able to go into offices, where there are dozens of computers, without wearing protective gear.”

Bill Ruck, principal engineer at CSI Telecommunications, a firm that does radio communications engineering, added: “Saying that 100 devices is 100 times worse is factually incorrect. Noise from these devices increases less and less as you add more.”

Bilton doesn’t mention what anyone who took undergraduate physics knows: the inverse square law, which applies to gravity, light, sound, and all electromagnetic radiation, where the force involved is inversely proportional to the square of the distance involved. This means that there is a steep fall off of the power of any radiating source with distance. That’s why theatrical spotlights are less intense on the stage than at the light source, or why magnets attract (or repel) objects close to them but not those farther away.

The same holds with electrostatic force, which is known as Coulomb’s law.

via Wikipedia

Coulomb’s law states that: “The magnitude of the Electrostatics force of interaction between two point charges is directly proportional to the scalar multiplication of the magnitudes of charges and inversely proportional to the square of the distances between them.”

So, anyone with a moderate exposure to college physics would have predicted the results from the EMT labs. But that won’t lead to any change at the FAA, because we live in la-la-land, where science has no hold and dark age superstition is law.

(Source: underpaidgenius)