Spirit Airlines

Spirit Airlines entered seven new markets last year. Don't look for that to happen again in 2020. The airline's network is reaching maturity.

Spirit Airlines is taking delivery of new aircraft, so this is an easy time for the airline to add more comfortable seats. The big question is will the airline pay to retrofit older jets to new standards? That's an expensive proposition, but it would show the airline is paying attention to passenger desires.

Spirit's decision to buy more airline technology from Sabre signals two things. Sabre has overcome a sales slump. And Spirit is investing to cope with its growth.

Every airline executive knows how to improve on-time performance. But there's a problem. It's expensive, since airlines usually must add slack to the schedule. Eventually the costs add up so airlines reduce the slack, hoping reliability will hold steady. Sometimes this works. Sometimes it doesn't.

In many ways, the airline had a solid quarter, but some potential long-term issues are starting to emerge, casting doubt on future performance.

This week in aviation, Spirit Airlines gets revenue increases by charging extra for non-seat purchases, Southwest makes a smart business move to attract new customers, and American Airlines makes it clear Mesa Airlines had better start improving.

Almost everything is improving at Spirit Airlines. Its on-time performance is getting better, and customer satisfaction is rising, according to the airline. More importantly for investors, ancillary revenue is up. Can the good times last?

The old idea of payments in monthly installments is seeing new life in the U.S. online travel sector. Uplift is one of the leading tech vendors powering loans to travelers for buying from airlines such as Spirit and search sites like Kayak. Expect a lot of marketing around this in 2019.

It was not clear three years ago whether Spirit could make it long term. It ran a shoddy operation, and it had alienated many of its customers. But Spirit is back, and it's making good returns for shareholders.

Spirit Airlines increasingly aims to prove it is possible to be cheap and loved.