Federal regulations forbid making calls from cellphones while aboard U.S. commercial planes in-flight, but Wi-Fi services could eventually make it possible for airlines to offer passengers the option of making voice and video calls over the Internet -- for a fee.
Airlines are struggling to make in-flight Wi-Fi profitable, and some analysts have suggested the airlines need to provide more than the email and Internet browsing offered on some flights using services from Gogo and Row 44.
The question boils down to whether U.S. travelers -- and airline flight crews -- would want to put up with people who talk on the phone during flights, analysts and airline officials have said.
Airlines in many countries outside the U.S. have allowed in-flight calls for two years or more, often using a system that securely and safely channels the wireless signal from a passenger's device through a router on the plane to satellites or towers on the ground.
For example, Geneva-based in-flight GSM and Wi-Fi provider OnAir (download pdf) lists 25 airlines, including AirFrance and British Airways that use its GSM service for voice calls, with callers billed at international roaming rates. Passengers can also use OnAir's in-flight Wi-Fi to surf the Web and read email.
"In-flight voice is an interesting topic," said In-Stat analyst Amy Cravens. "Airlines for the most part [especially in the U.S.] continue to resist it to preserve the passenger experience, but many travelers indicate they would want the service."
Cravens and other analysts say there's no danger of in-flight Wi-Fi interfering with a plane's communications or navigation systems. Many experts also say that regular cellphone calling without Wi-Fi is safe, but the Federal Aviation Administration and the Federal Communications Commission still ban the service.
The FCC reconsidered its ban and launched an inquiry in 2004, and in 2007 the agency ended up keeping the ban in place, saying there wasn't enough technical information on whether cellphone use onboard aircraft would cause harmful interference to ground-based networks.
The FCC's position led to a public debate over in-flight cellphone usage in 2007. There were suggestions at the time that continuing the ban simply gave the airlines an opportunity to find ways to charge for calling services.
But using a Wi-Fi channel for voice or video calling opens up many possibilities, as long as the airlines and the public want to head in that direction, analysts said.
"From a technical perspective, there is no concern [of voice over Wi-Fi] interfering with operational communications, so it is more of a security and passenger experience matter," Cravens said. "I have not seen any movement on this topic by either the FAA or airlines, but would not be surprised if eventually the ban is lifted."
Jack Gold, an analyst at J.Gold Associates, added: "I've never seen actual credible proof that cellphones on planes caused any interference problems. So in my opinion, turning off your phone on a plane is an unnecessary requirement."
Gold added that many people probably forget to turn cellphones off during flights, despite reminders by the cabin crew.
Analysts said some law enforcement and government security agencies have worried that terrorists could use in-flight calling systems (either via Wi-Fi or cellular service) to coordinate an attack from a plane. U.S. Department of Homeland Security officials did not respond to a request to comment on that matter, however.
The U.S. airlines have the biggest stake in the question of whether to allow voice or video calling at some point, perhaps using a secure and safe system and charging people who choose to use it. Computerworld contacted several airlines, including American and United, to ask their position on the matter, but none responded.
Matt Hamblen covers mobile and wireless, smartphones and other handhelds, and wireless networking for Computerworld. Follow Matt on Twitter at @matthamblen, or subscribe to Matt's RSS feed. His email address is firstname.lastname@example.org.