For years, the biggest question about airline WiFi sounded more like a lament: Why is it so bad and so expensive?

The answer was a simple story of supply (not enough) and demand (way too much), with some technical wrinkles tossed in. But these days, the word about in-flight Internet is surprisingly optimistic — if wildly inconsistent.

“The quality is generally pretty good, but it really varies by region, airline, size of aircraft, [and] where the airline is operating,” says Jason Rabinowitz, who keeps track of airline amenity information for travel technology company ATPCO. “It’s a really dynamic thing whether your complaint about WiFi is valid.”

The improvement over the past few years is due to a widespread shift from old systems that used towers on the ground to satellite-based models, an update that airlines have been making for much of their fleets. American Airlines, for example, said Monday that more than 700 planes — pretty much its entire narrow-body fleet, aside from planes retiring soon — had been outfitted with satellite-based WiFi, a project nearly two years in the making.

“We did a good job of training people that the Internet was slow and expensive on a plane,” says John Wade, president of commercial aviation at Gogo, the best-known name in airline WiFi. “We now need them to realize that they’re in a different world today.”

Even the old-school technology is getting an upgrade, though that’s a couple of years from ready. Gogo announced late last month it would introduce a faster 5G network for the smaller jets that use air-to-ground systems in 2021. That includes regional planes, private jets and smaller mainline aircraft.

“Generally speaking, the newer satellite systems are faster than the ground-based systems, and then the ground-based systems are in the process of being upgraded so that they will be faster,” says Seth Miller, an analyst who covers in-flight connectivity systems for publications including

Although experts agree that the technology is far better than it used to be, there are still plenty of opportunities for fliers to be extremely frustrated. The recently released J.D. Power 2019 North America Airline Satisfaction Study calls out in-flight services, including connectivity, as the lowest-ranked factor in the survey.

In a report at the beginning of last year, Routehappy — which provides content about amenities on airlines that passengers can buy — showed that 82 airlines worldwide offered in-flight WiFi. Of connected flights, service that was “basic” was available on 27 percent of available seat miles, “better” was on 57 percent and “best,” meaning capable of advanced media streaming, was on 16 percent.

The company, bought by ATPCO last year, gathers data about in-flight WiFi for airlines around the world and matches it with flight schedules so travelers can find out which flights will be connected. Those who can’t be in the air without a signal can check popular booking sites, including Google Flights and Expedia, to find out which flights should have WiFi.

“The story is less of ‘Why is it so bad?’ to more of ‘How do I find the good WiFi?’” Rabinowitz says. “It is out there, and it does work, and typically it does work well; you need to make sure you’re booked on a flight that has it, which is getting a lot easier these days, especially if you’re flying in North America.”

Rick Baldridge, president and chief operating officer of communications company Viasat, says travelers aren’t content to fly without the consistent option to connect anymore. His company provides WiFi on more than 1,300 planes, including JetBlue’s free service.

People “fly on an airline that has it, then they fly on an airline that doesn’t, then they fly on an airline [with service] that doesn’t work,” Baldridge says. “This is a groundswell of consumers that are demanding connectivity.”

Still, even when the good service is working perfectly, Miller says, no one should expect to “download hundreds of gigabytes of data over the WiFi connection on the plane.” But they should be able to stream a movie “reasonably well,” check email, and browse and use social media.

“Those things all work pretty well on the newer systems — but only pretty well,” Miller says. “There are still inconsistencies, there are still times when things flake out. … We’re still in the situation where none of them are perfect, and they’re never going to be.”

Some airlines are introducing faster new systems but still have older models in place on part of their fleet. Regional jets, which are too small to accommodate the new satellite technology, still generally operate on the slowest system. Pricing is all over the place, depending on which airline you fly. JetBlue is the only U.S. airline with free WiFi across the board, while Delta recently piloted free service on some flights. The rules about what you can do with the WiFi vary as well, and the sign-in process can be clunky.

Internationally, coverage is hit-or-miss; global carriers have been slower to roll out fast service, or any service, than those in North America. Even well-equipped domestic carriers come with an asterisk: JetBlue, for example, notes that it only provides WiFi for flights over the contiguous United States. Its coverage area will expand to some international routes as newer planes start flying but still won’t include destinations in South America.

Even so, the airline warns: “Due to weather and other variables, this coverage area does not necessarily guarantee service availability.”

Those variables can include too many planes in the vicinity trying to use the same satellite, the lag that can happen when planes move from one satellite’s coverage to another, or just general technical bugginess.

“500 miles an hour, five miles above the Earth, everything gets complicated,” Miller says.

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