super linear scaling and the network effect

'Super-linear scaling' is the generic descriptive term that complex-systems folk use to talk about a wide variety of phenomena, including both network and non-network effects. (VMT:population is characterized by super-linear scaling, for example).

The number of passengers at any airport has a number of causes, but can likely be attributed to one of two factors: local demand and the agglomeration economies offered by by massification. Local demand is probably itself non-linear: larger metro areas tend to be richer, richer areas tend to fly more. But massification is probably the main driver. Cost per flight rises with the square of area, but passengers per flight rise with the cube of area. Big planes are more efficient. So the hub-and-spoke model uses small planes to massify into large vehicles. The efficiencies are such that SLC-DC flights often take me through LA. That said, there is indubitably some advantage to being on the way: I spend a lot of time waiting for flights in Detroit, Chicago, Atlanta and DFW.