Date of Award


Document Type


Degree Name

Master of Science in Systems Engineering


Department of Systems Engineering and Management

First Advisor

Michael E. Miller, PhD


The Air Force employs ejection seats in its high-performance aircraft. While these systems are intended to ensure aircrew safety, the ejection process subjects the aircrew to potentially injurious forces. System validation includes evaluation of forces against a standard which is linked to the probability of injury. The Muti-Axial Neck Injury Criteria (MANIC) was developed to account for forces in all six degrees of freedom. Unfortunately, the MANIC is applied to each of the three linear input directions separately and applies different criterion values for each direction. These three separate criteria create a lack of clarity regarding acceptable neck loading, leading to potential disputes during acquisition. Thus, the current research sought to adjust the MANIC formulation to provide clear, easy to interpret criterion values, a single MANIC formula independent of the direction(s) of input acceleration. We developed an optimization program that would run the survival analysis for each of the input axes.

AFIT Designator


DTIC Accession Number