For onboard Wi-Fi, not all airlines are equal

Best and worst airline wi-fi
Best and worst airline wi-fi

Nothing ruins an otherwise productive workday like the hours of dead time on a plane without Wi-Fi.

Onboard Internet is an engineering marvel—it's either beamed up to a plane's belly (or side) from hundreds of ground towers or bounced off a handful of satellites from above. But as most business travelers have experienced, it's hard to get the kind of speeds that most people take for granted on the ground, and access is often expensive.

Airlines in the U.S. have committed billions to providing a better in-flight experience, and each company has made slightly different bets on their Wi-Fi business plans. Here is where each airline stands for domestic flights, based on all domestic flights on a given day from air travel analytics site Routehappy.

If you booked a random domestic flight on July 6, you would have about a 60 percent chance of finding Wi-Fi onboard. The best bet overall would be to pick a Virgin America flight.

All of Virgin America's planes are equipped with upgraded air-to-ground antennas from Gogo (you're probably familiar with the company, which effectively founded the industry in 2008).

Those connections use similar technology to a 3G cell phone. They may be triple the speed of the first generation, but you shouldn't expect to be streaming any videos—the peak download speed is much slower than the average home or smartphone connection, and it has to be shared with everyone else on the plane.

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"Passengers are expecting more and more capacity, more and more bandwidth, just like they experience on the ground," said Steve Nolan, spokesman for Gogo.

Of course, while Virgin's 100 percent Wi-Fi coverage is impressive, the airline is tinier than the rest with only about 50 aircraft. Delta, which has more than 5,000 flights scheduled for the day tested, may be the most impressive overall with 80 percent coverage.

But most of the airlines are offering speeds that wouldn't satisfy today's user. Even Southwest, which uses a newer satellite system, doesn't offer high speeds—perhaps because the bandwidth isn't worth the cost.

For the fastest internet, a traveler should go with United or JetBlue. JetBlue, one of the last major American airlines to add Wi-Fi to its flights, uses satellite technology that can stream video, and it recently made a deal with Amazon for content.

United, which is the unique position of having three different internet providers, has the overall lowest chance of providing internet to our domestic traveler. The airline was slow out of the gate in adopting Wi-Fi, but it has focused on outfitting its entire fleet in recent months and has seen the most growth overall.

The United States leads the world in on-board Wi-Fi. That's because the country has a large contiguous landmass—perfect for the early ground-to-air technology offered by Gogo's 250 towers.

"Because we've had this legacy network since 2008 or 2007, the U.S. is the most saturated," said Jason Rabinowitz, data research manager for Routehappy. "No other region in the world even comes close."

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As for the airlines, Rabinowitz said that they all have been innovative in Wi-Fi in their own ways. American was an early adopter, Delta has constantly upgraded its systems, and JetBlue has the fastest connections (even if they risked losing customers for years before finally providing access), he said. Delta has already committed to upgrading 250 aircraft with Gogo's new satellite-based system next year.

"Every major airline in the U.S. is going out of their way to roll these systems out quickly on every aircraft," said Rabinowitz. "Each airline has chosen a different path, and we'll see which is best."

Faster Internet to come

For now, most connections are slow, and getting access tends to be expensive. The price, at least, is by design, said Nolan. Charging more for usage manages the network so passengers have a usable experience every time they fly, he said.

Some commentators have suggested that the low percentage of people on a flight using Internet—around 7 percent—means that customers aren't interested in paying for on-board internet. In reality, keeping that rate low with high prices is the best way to deal with bandwidth limitations until newer systems come online, said Nolan. Rabinowitz agreed—Americans want Wi-Fi.

"They're so accustomed to having it, it's an afterthought for them," said Rabinowitz. "They might not even think that it might not be offered."