Why should we use jumbo jets, instead of sail ships? There is a cost function associated with time. For most people, there is a threshold after which further g

Why should we use jumbo jets, instead of sail ships? There is a cost function associated with time. For most people, there is a threshold after which further gains become insignificant per hour saved, so a Jumbo jet is not much better than a super sonic plane. But the world has also changed since the Concorde, and maybe now there's a bigger market for people for whom getting something or someone across the Atlantic in a few hours is important: Let's say, for example, that a loved one is severely ill, and you need to get there fast to say your goodbyes.