ULCC can really work well, but it needs the whole company to stay disciplined. For us pilots, ULCC usually makes us focus on saving fuel, and it’s more than just a suggestion—it’s enforced because that’s where the big bucks are. Airlines using ULCC strategies worldwide have some pretty strict fuel policies. They often set specific CI speed limits unless ATC says otherwise, require flaps 3 for landings, have packs off during departures without APU, minimal APU usage and encourage one-engine taxiing, among other things. These aren't just guidelines; airlines actually keep an eye on pilots monitoring personality who don’t stick to the rules. When they crunch the numbers, they see that operational costs have to be kept really low—otherwise, investors lose interest, and the airline could struggle to survive. ULCC can be profitable, but it’s got to be managed right since the profit margins are super tight.
Let's assume a 700 departure day, if they can save 100lb each leg, it's 70.000lb in one day alone or 25.550.000lb of fuel per year.... just 100lb per leg means millions of dollars in a year..... for a business with such tight margins this is big a deal. That's how ULCC Business are.... penny by penny.