> I want to assume there is some good reason that is not, "we didn't want to pay for more runway" This is how the entire world of engineering works. Overbuildi

> I want to assume there is some good reason that is not, "we didn't want to pay for more runway" This is how the entire world of engineering works. Overbuilding everything is much worse for society due to the massive costs. Doubling runway lengths cumulatively would consume hundreds of thousands of acres in the US alone. Many of these airports are right in cities so you’re talking about displacing hundreds of thousands of people. If you could stomach that, airlines with real engineers would just calculate that they can now land much larger and/or heavier loaded planes and do such.