Right after stowing the tray table and before bringing the seat back up, fliers of all shapes and sizes are politely ordered to turn off everything from laptops to PlayStation Portables. These rules, enacted long before the no-liquids, post-9/11 world of today, hark back to a simpler time of aviation passenger safety.
One of the ways the Federal Aviation Administration keeps air travel safe is by mandating that the airlines minimize electromagnetic interference as well as stow anything that could knock someone in the head during takeoff and landing. The “Use of Portable Electronic Devices Aboard Aircraft” regulation, first enacted in the early 1960s and last updated in 2006, kills both those birds with one stone.
“The two-edged sword is, as we’ve done better and better about making [flying] safer, it becomes more normal for people to expect it to be safe,” says Dave Carson, an engineer at Boeing and co-chair of Special Committee 202, a group within the non-profit RTCA that advises the FAA on portable electronics.
The rule states that turning off music and computers has a lot to do with making sure everyone is paying attention. Take-off and landing are the most critical times during the flight. If a member of the flight crew needs to make an important announcement, he does not want to compete with Jay-Z for your attention.
Carson says there is also a physical component to stowing laptops and smaller electronics. Anything that can bounce around during a rough landing should be put away, he says, even books and magazines—although they are not included in the electronics regulation.
The second part of the ruling relates to electromagnetic interference. Boeing has found that cell phones’ signals can operate on the same frequency as airplane navigation bands. But iPods, and any other electronic device that may not be sending out a deliberate signal, also have some potential to get in the way of navigation equipment. But it is unclear and almost impossible to quantify how big the risk is, even to the companies that make and operate the aircrafts. Despite only a minute risk, airlines must exercise caution.
“The GPS are looking for extremely small signals very far away, and if you have something on your plane [interfering], it could be a problem,” Carson says. That risk is very small, however. Boeing has even tried to replicate specific scenarios when portable electronics were blamed for interference, such as a plane taking a shallow turn because someone was using a handheld computer on board. In almost all scenarios, the interference from a computer or music player could not be proved.
Equipment such as GPS, the Instrument Landing System and Glide Slope System are all manufactured to withstand electromagnetic susceptibility. But when the airplane is within 10,000 feet of the ground, multiple systems are in use. If many passengers use their PDAs at the same time, there is more electromagnetic interference to contend with, and the flight instruments would theoretically be more at risk to malfunction.
Risk also varies with the age and model of aircraft. While an older airplane that has not been updated may be more susceptible to interference, newer instruments are generally more sensitive. Even so, the rule is precautionary. “There has never been an accident related to an electronic device interfering with the [airplane instruments],” says Steve Lott, spokesperson for the International Air Transport Association, an airline trade group.
The biggest concern these days for Special Committee 202 is the devices that have wireless technology, or Wi-Fi, that the consumer may not even know about when they buy it. Many PDAs and portable game consoles are Wi-Fi enabled, and RTCA works with the Consumer Electronics Association to provide recommendations for companies that manufacture products with Wi-Fi so it can be easily turned off. iPhones have a distinct ‘airplane mode’ that disables the networking capabilities, allowing applications on the phone to be used safely during flight.
As electronics become integrated to include phones, games, email and computing in a single device, the office is everywhere. “The general flying public think of the plane as just one more place where I do business or leisure activities,” Carson says. But the runway is not Starbucks. And even with the litany of more alarming security concerns, keeping those electronics off while near the ground is still a part of safe flying.
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