A new low-cost airline coming to Logan airport, Primera Air, will fly nonstop to Paris and London for as low as $99, but the fare comes with some caveats.

Seat selection, a checked bag, a meal—that could all add $130 to the low fare.

Still, for travelers willing to go bare bones, starting in May 2018, there will be three low-cost choices at Logan, with Primera joining Norwegian and Wow.

Patrick Smith is a pilot and industry analyst who runs a blog called "Ask The Pilot." He says part of what's contributed to the rise of low-cost, no-frills airlines— especially long-haul, overseas ones — is plunging jet fuel prices that have made their business model viable.

But, Smith says, "If and when fuel prices start to climb, I don't know that all of these low-cost airlines are going to be able to survive."

Smith says the availability of more low-cost airlines at Logan is part of what he calls an "astonishing" long-term expansion of overseas flights in general at the airport.

And, he adds, while a rise in fuel costs could knock low-cost airlines off the map, flyers are still enjoying fares that are a fraction of what they were 30 years ago.

It's not only the low-cost airlines that are charging extra for what used to be standard. Smith says established "legacy" carriers have been 'unbundling' their services too. And while it may be an annoyance to some, he says, "those extras that you're paying for one at a time now, those things were never free. They were part of the air fare — you used to pay it all at once instead of in pieces, but it was always there."

With the legacy carriers unbundling, and low-cost carriers being forced to offer more than bare-bones — Primera has wifi on all its Logan flights to Europe —Smith says they're starting to meet in the middle.