General Methodology

Multipoint aerodynamic optimization can generally he described in the form of reference (353|:

I. Select objective function.

2. Select variables and constraints.

3. Select optimizers).

4. Optimize and analyze the results.

16.3.1 Drag as an Objective Function

Consider the objective function О described by the total energy loss due to aircraft drag during the operation of the aircraft over n missions:

In this expression./^ is the probability of mission i. and r is the block range for that mis­sion. This expression can be simplified by weighing the drag over a number of representative de­sign points:

m

о = X и’.со (107)

I В I

In our experience, five design points are enough to describe a multipoint design ade­quately.