FCC Taking Sensible Path to Study Mobile Phone Use on Airliners

NEWS ANALYSIS: The Federal Communications Commission has formally decided to study the possibility of allowing the use of cellular connected phones and computers on board airliners.

Before you start making voodoo dolls in the likeness of Federal Communications Commission Chairman Thomas Wheeler, take a minute to find out what the FCC actually did in its Notice of Proposed Rulemaking (NPRM) regarding the use of devices using cellular technology on airliners.

First and perhaps most important, it expanded the existing ban on wireless devices on airplanes. Yes, that's right, expanded. Previously, the FCC's ban only applied to devices operating in the 800MHz cell phone spectrum, a limitation left over from the dark old days of analog phones.

The new rule expands that limitation to all mobile devices using cellular technology, regardless of frequency. But it also did something that has people freaking out. It allows airlines, under certain circumstances and with significant limitations, to provide special equipment that will allow the use of mobile devices using cellular technology. Those devices can include mobile phones as well as tablets and computers that use cellular technology.

What the new NPRM does not do is require the airlines to do anything to allow cell phones. Instead, it opens up a period of investigation along with a public comment period that will eventually lead to revised FCC regulations on the topic. The FCC is simply changing its rules to keep up with the technology in the 21st century.

The original reason for the cell phone ban on aircraft has nothing to do with your seatmate noisily blabbing away on a mobile phone. It has to do with preventing interference with the electronic equipment on the airplane and preventing interference with terrestrial wireless networks. While this ban originated in the days of analog phones, it remains to this day because cell networks aren't designed to work with airplanes.

The reason that airborne cellular devices cause problems with terrestrial networks is because the cell systems' computers will sense a weak signal coming into many towers at the same time. This signal will be traveling at hundreds of miles per hour, and will be lighting up a swath of towers as it does. But the cellular radios in those towers are outfitted with antennas that basically point at the ground. The result is that the networks' computers won't know which tower is closest, and as a result it will order the device on the airplane to boost its transmitting power.

The higher transmitting power raises the likelihood that cellular devices on airplanes will interfere with the electronic equipment providing navigation and communications for the aircraft. This is not a good thing.

Wayne Rash

Wayne Rash

Wayne Rash is a freelance writer and editor with a 35 year history covering technology. He’s a frequent speaker on business, technology issues and enterprise computing. He covers Washington and...