Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


Department of Operational Sciences

First Advisor

Jeffery D. Weir, PhD.


Because of their versatility, advanced composite materials are being used at an increasing rate in the manufacturing of aircraft, as well as other products, such as autos, sporting goods, and medical products. Airframe structure materials used throughout aerospace manufacturing processes consist of significantly greater percentages of advanced composite materials. However, these manufacturing processes and the associated reduction in part counts are not considered in the aircraft procurement and life cycle cost (LCC) management processes in the United States Air Force (USAF) community or the Department of Defense (DoD). This situation led the leaders of USAF and DoD to restudy the LCC models that estimate the cost for most weapon systems. Most of the present LCC models and procurement processes were developed and established when the metals were used in airframe structures. Over the last three decades, a series of composite affordability initiatives (CAI) has culminated in a better quantifying system for calculating the influence of advanced composite materials in airframe structures. This research finds that significant relationships exist between part counts, touch labor hours of development, and production cost. The reduction in the part counts led to corresponding reductions in touch labor hours. This research effort was undertaken to update the cost estimating relationships (CERs) for airframes by including the part count percentage reduction (PCPR) cost factors of the above mentioned relationships. The results suggest that the reduction in part counts forces a related percentage reduction in touch labor hours cost categories. The output of this research is the recommendation that the present LCC estimation models for advanced composite aircraft be upgraded.

AFIT Designator


DTIC Accession Number