Aircraft Airframe Cost Estimating Relationships

This report presents generalized equations for estimating the development and production costs of aircraft airframes. It provides separate cost estimating relationships (CERs) for engineering, tooling, manufacturing labor, and quality-control hours; manufacturing material, development support, and flight-test cost; and total program cost. The CERs, expressed in the form of exponential equations, were derived from a database consisting of 34 military aircraft with first flight dates ranging from 1948 to 1978. In addition to the basic objective of developing an updated set of airframe CERs, the study also examined three specific possibilities for improving CER accuracy: (1) stratifying the full estimating sample into subsamples representing major differences in aircraft type; (2) incorporating variables describing program structure and airframe construction characteristics; and (3) for the fighter aircraft only, incorporating an objective technology index into the equations.