Chris​Hubbs​.com

The FAA announced today that it is directing airlines to enact policy that will allow passengers to use their mobile devices (smartphones, tablets, etc) from gate to gate - a welcome change for travelers who are used to the “turn everything completely off until we get above 10,000 feet” announcement at the beginning of every flight.

So my first thought comes as a frequent traveler on this nation’s airlines, and I can summarize it like this:

It’s about time.

But what about the concerns over device usage? The FAA has said for years that they thought it was possible that having phones turned on during takeoff and landing could affect the aircraft. Is that really not the case?

Now, before I start offering opinions, I should explain that I have a little bit of background on this topic. I work for a company that designs and manufactures avionics equipment for big (and small) aircraft. We build things like displays, autopilots, communications radios, and GPSs for just about every aircraft manufacturer you could name. I work in our Certification Department. While my specialty is software certification, I work every day beside men and women who are some of the foremost industry experts in hardware testing relevant to concerns over the use of mobile devices.

Usual disclaimer: all the opinions in this piece are mine, do not necessarily reflect that of my employer, the FAA, or anybody else in the whole wide world.

First off, I’ve had discussions with these guys about the use of mobile devices on board, and they seem wholly unconcerned. That’s a significant data point in my mind. Second, I’ve flown multiple times on our corporate jet with our lead FAA-authorized test pilot flying the plane. Never has he expressed any concern that we make sure our cell phones are turned off prior to takeoff. (I try to make sure to kick mine to airplane mode just so I don’t drain my battery while searching for signal!)

Secondly, I’ve seen the test reports on how this hardware is tested.

Every critical piece of equipment that’s going on the aircraft has to go through a challenging set of qualification tests. The exact tests will be dependent on the how the equipment will be used (for instance, you don’t need a sand test for a box that’s only going to used on the inside of a 747, but you would if it were mounted external on a helicopter), but you’re always going to have to test it for things like vibration, temperature (bake it and freeze it!), and (most pertinent to this discussion) Radio Frequency susceptibility.

I’ve seen the pictures of the test setups, and while I can’t show them to you directly, here’s the general idea of what they do:

In this example, Dr. Doofenshmirtz is the tester, and the unit under test (display, autopilot, etc) is sitting on the table, while Agent P sits there monitoring to make sure it continues to run correctly while the Evil-Inator (or some similar sort of radio transmitter) beams radio waves at it.

(I’m not exaggerating much here.)

To pass these tests, the unit under test must work correctly while being bombarded with a whole range of radio frequencies. If it stops operating correctly, stop the test, update the hardware, and try again.

There’s a reason they test avionics this way, and it’s not because they’re afraid of people who forgot to turn off their cell phones. Airplanes frequently fly past radio transmission towers, and not infrequently through electrical storms. You want to be sure that you’re not going to lose all of your displays and controls even in a freak situation.

The systems design to perform the most critical functions on the aircraft are carefully designed and analyzed to ensure that they will fail no more often than once every one billion flight hours. That’s an amazing standard, more stringent than any other industry, save maybe nuclear. The engineers I know who design systems like our autopilots are some of the finest engineers I’ve ever met.

So suffice it to say I’m not particularly worried about being on a plane where everybody is allowed to have their iPhone or iPad or Kindle turned on during roll-out.

According to that CNN story, Delta Airlines has already filed plans with the FAA to allow their passengers to use devices below 10,000 feet. I’m excited to hear that. I don’t know how fast the FAA will move, but.. I’m flying to Florida next Monday for work, and I’d love to be able to keep reading my e-book or watching my movie from boarding all the way through arrival.