CMU group finds danger increasing

Wednesday, March 01, 2006

By Mark Belko, Pittsburgh Post-Gazette

You might want to think twice the next time you`re tempted to make a call from your cell phone during an airplane flight. Or flip on your portable game player. Or work a spreadsheet on your laptop.

Besides possibly annoying fellow travelers and breaking federal regulations, you might be endangering the airplane, according to a Carnegie Mellon University study that quietly monitored transmissions on board a number of flights in the Northeast.

The study, by CMU`s Department of Engineering and Public Policy, found that the use of cell phones and other portable electronic devices can interfere with the normal operation of critical airline components, even more so than previously believed.

Researchers concluded that such devices can disrupt the operation of cockpit instruments, including the Global Positioning System receivers that are becoming more common in helping to ensure safe landings.

Researchers noted that there is no definitive instance of an electronic device used by a passenger causing an accident. However, they said their data support the conclusion that use of devices like cell phones ``will, in all likelihood, someday cause an accident by interfering with critical cockpit instruments such as GPS receivers.``

The findings come as the Federal Communications Commission is considering lifting the ban on the use of cell phones during flight.

Both the FCC and the Federal Aviation Administration have barred the in-flight operation of cell phones because of concerns about interference, both to navigational and communications equipment in the air and to cell phone towers on the ground.

Verizon`s Airfones, the devices typically found on the backs of passenger seats in some aircraft, operate at frequencies that do not interfere, and have been on some planes for more than a decade.

Airlines typically allow the use of portable electronic devices, like game players and DVDs, above 10,000 feet, but not during takeoff or landing. Laptops also can be used, but not for communications purposes, such as sending or receiving e-mail.

In the past, the FAA has found nothing to indicate that the use of passive devices like laptops or game-playing electronics poses a threat to the aircraft.

However, the CMU study concluded otherwise. While the researchers looked primarily at cell phone use, they also discovered that emissions from other portable devices proved ``problematic.``

``We found that the risk posed by these portable devices is higher than previously believed,`` researcher Bill Strauss said in a release announcing the findings.

And despite the ban on cell phone use during flights, the researchers discovered that on average one to four cell phone calls are made from every commercial flight in the northeast United States.

Some are even made during critical flight times, such as the climb after takeoff or the final approach.

The study is featured in an article in the March issue of IEEE Spectrum, a monthly magazine for technology professionals.

The study was conducted over three months in late 2003 with the cooperation of the FAA, three major airlines and the Transportation Security Administration.

During that period, the researchers monitored radio emissions from cell phones and other electronic devices on commercial flights throughout the Northeast. The equipment used to take the measurements, including a laptop computer, had been modified for safe in-flight use and fit in a nondescript carry-on bag.

While the data date to late 2003, the researchers said they believe the study is the first to document in-flight emissions of portable electronic devices.

In response to the findings, they recommended better coordination between the FCC and FAA in developing electronic emissions standards. They also called for the routine monitoring of on-board radio emissions and the deployment of equipment that would allow flight crews to determine if a passenger is using a cell phone during final approaches.

They also recommended against lifting the ban on cell phone use. The issue is still under review by the FCC, a spokeswoman said.

The FAA, which also would have to approve lifting the ban, has said as recently as July that it opposes a change in the rules.