Brian Sumers

For years, airline passengers have hated Gogo's air-to-ground, or ATG, service. But change is coming, and travelers soon may not need to curse when they learn they're on an air-to-ground-equipped airplane.

You might find the customer experience to be the most interesting aspect of an airline. But real aviation nerds obsess over airline schedules — where an airline flies, when, and with what plane.

Many airlines sell premium amenities to customers in coach. But is it worth it? Yes, these are high-margin items, but airlines don't sell that many of them. Most coach customers want only the basics and don't want to pay extra for anything.

If you're an investor, it's not clear Spirit's model is the right one. But if you're a passenger, you should love the airline, even if you never fly it. Spirit is responsible for many of the U.S. fare wars we've seen in recent years.

Even if they buy first class pajamas, an upgraded meal, and an amenity kit, coach passengers still won't feel like they're in a premium cabin. But at least some airlines are giving travelers the chance to buy up to a better experience. It's cheaper than an upgrade.

Sometimes you'll buy a plane ticket and the airline might try to sell you a rental car. Other times, the airline will skip the car but ask if you want premium economy. Why? Carriers are using data to guess what extras you might buy.

Like most airlines, Air Canada knows a lot about its customers. But in 2020, once it launches a new loyalty program, it will have more flexibility to slice and dice data to deliver personal offers to passengers. Let's hope customers don't find it creepy.

Most airlines are not advanced with their e-commerce strategies. Many have done OK without refining how they sell their products. But if they want to succeed in the long term, they probably must become more sophisticated in how they reach customers.

In a lengthy soliloquy on American's first quarter earnings call, CEO Doug Parker indirectly told investors to relax. Yes, U.S. airlines are increasing capacity this year. But they're being prudent by solidifying their hubs, he said, and not repeating past mistakes.

JetBlue is the latest airline to fall behind on a cabin retrofit program. It happens sometimes, as it's not so easy to update airplane interiors. But the first plane is in the shop. Considering JetBlue has some planes that haven't been touched since the early 2000s, this is welcome news.