The Design Importance of Airplane Mile Costs Versus Seat Mile Costs

It is shown that the airplane design factors affecting direct operating cost may be isolated into two major categories:

1. 1.
   Airplane size
2. 2.
   Technology and configuration

In the first category the effect of design pay-load and design range on airplane mile and seat mile costs, profit potential, and productivity are discussed. The airline planning factors of traffic density, frequency and load factor are shown to have the principal influence on airplane size.

In the second category, the effects of technology and/or configuration differences on D.O.C. are shown as factors independent of airplane size.