Answer:
Economic considerations must be considered when designing a model.
Step-by-step explanation:
The engineers wanted to use a specially formulated glass which was lighter than ordinary glass for the design requirement of light weight and portability with helicopter. However the cost was very high than the budgeted amount for the material to be used in the project. The alternative was to use a plastic wind shield. In design perspective considering the weight and portability criteria, this will still work .In the economic perspective, the budget will fit. This concludes that economic considerations must be considered when designing a model. Though this factor might not be the most important one , but it helps in ensuring projects budgets are within expected margins.