That sounds backwards. Airports get built as close as possible to the cities they serve. For newer airports that ends up being some distance away because they need to avoid existing homes.
> You distribution center needs ready access to transportation, it doesn't have to be next to your consumers. We are not delivering packages to their destinations with planes, after all. Usually trucks do that.
The point of the plane is to save on trucking time though, so you want a distribution center fairly close to population centers.
Airports get built "far away" in the sense that, between land prices and noise abatement, airports are generally on the very outskirts of a city at the time they are built and the city's central train station will be much closer to the city centre.
But apart from military bases on remote islands, no airports are so remote that "don't worry where you ditch the plane if there's a problem, there's nothing near the airport" would be an option :)
Are they?
I'd argue that they generally aren't... except that, over time, cities may grow until they are right next to the airport again. And then new airports get constructed - usually far away.
> terms of freight
Only for certain classes of freight. You distribution center needs ready access to transportation, it doesn't have to be next to your consumers. We are not delivering packages to their destinations with planes, after all. Usually trucks do that.
> If your plane can't add velocity, your ability to plan _anything_ is severely curtailed.
Not an issue with pre-planned routes. There can be contingencies in place for malfunctions at any stage in the flight.
I wouldn't worry too much with engine failures and the like. Worry about sensor problems.