The walls have ears—even at 30,000 feet.
An investigation by the Intercept and French newspaper Le Monde reveals that British and American spy agencies used satellite systems to keep track of cell phone use aboard passenger flights from as far back as 2005.
Many airlines now offer in-flight phone and data services. But airplanes have been fitted with on-board GSM systems that allowed them to provide mobile connections since the mid-2000s.
Even though passengers weren’t always strictly allowed to make phone calls on flights back then, people had increasingly begun to realize that using a phone during a flight wasn’t necessarily as dangerous as they’d been led to believe. So if they had signal and could stomach the cost, why not make a call?
The spooks knew this too, of course, and Britain’s intelligence agency, GCHQ, and the NSA paid close attention to airborne callers. One National Security Agency document cited by the media outlets explains that the agency had already recorded data from 100,000 people who used their phones during flights by February 2009.
The two organizations appear to have used ground stations to intercept signals being transmitted between airplanes and satellites. The Intercept notes that the “simple fact that the telephone was switched on was enough to give away its position.” But they could also monitor usage, enabling them to log details about phone calls, text messages, and data transmission.
These days, with cellular connections widespread on airliners, such monitoring is likely to be commonplace—and, indeed, NSA records show timestamps and dates of phone calls made in recent years. So next time you’re tempted to make a mile-high phone call, you might consider just watching a movie instead.