Whether the long-haul, low-cost airline model works is one of the most-controversial strategic issues discussed in airline boardrooms. After all, if there were to be a second revolution in the airline business following the invention of low-cost short-haul routes, the impact on legacy carriers would be equally -severe. So it is no surprise that U.S. and European airlines are in a fierce lobbying campaign against Norwegian’s long-haul affiliate, -Norwegian Air International (NAI). And who knows where it might lead? 

As Aviation Week’s in-depth sector analysis shows, there are two schools of thought: One argues that what makes the model so good on short-haul routes cannot be transferred to the long-haul market. Others contend the low-cost principles can be used regardless of stage length, thus there is no reason why that segment of the market should feel secure.

The answer is probably this: Some principles can be used, and some others can’t. But the real reason why legacy carriers should not expect the same kind of revolution they have seen with short-haul is that they can easily copy whatever new product or strategy newcomers may introduce. 

The one major factor in favor of legacy carriers in the long-haul market is that few routes work without feed, even with very low fares. Consider Norwegian—it started out developing short-haul bases first at the airports being used for long-haul services to promote the brand and enable it to use feed. That greatly limits the number of destinations that make sense. There will not be a daily service from Perpignan, France, to St. Louis, for example. 

And there will not be ultra-long-haul services. As Air Asia X has found out the hard way, its European flights were a huge challenge to run economically. Agreed, the Airbus A340 clearly was the wrong aircraft, and the same routes flown with an A330neo may suddenly work well. But the industry agrees that below 10 hours is where most of the action should be. Airlines will have to offer food and entertainment, albeit maybe not free of charge. And most agree there will also be some form of premium offer that will be needed to make low-cost, long-haul service work economically.

So the legacy part of the industry will know roughly what the low-cost part could do across the Atlantic, or on long-haul Asian routes. Maybe more important, the legacy segment can react to aspects that are typical of low-fare carriers and would work in the long-haul market. 

Higher productivity is one example: While it is true there is not much potential left to keep widebody aircraft in the air for more hours per day in well-run networks, there are other means to improve productivity. Increasing cabin density to lower unit costs and grow revenue potential will clearly work. Already, airlines are studying ways to lay out cabins more efficiently to eliminate premium cabins where they don’t make sense or to squeeze in another seat per row for a nine-abreast economy section in the Boeing 787, where the manufacturer advertised eight. Some airlines have also seen success in negotiating new labor agreements that made cabin crew and pilots more productive. 

So much for the good news. The bad news is that there are already huge low-cost long-haul airlines in operation that are just not labeled as such. They are called the Big Three Gulf carriers. Depending on the route, Emirates enjoys unit costs around 30% below the level of European legacy airlines. To make matters worse, those cost levels are achieved despite the premium products the three airlines offer, which often are superior to what competitors provide. 

The Gulf carriers will not be a threat equally in each market, and the Europe-North America origin-and-destination traffic will likely be little affected. But the Gulf carriers remain a strategic threat that is much more serious. Not only because they are big but because, unlike the case of long-haul low-cost airlines, there is little legacy peers can do to adapt. 

A version of this article appears in the February 2-15, 2015 issue of Aviation Week & Space Technology.