<p>Military aviators are commonly exposed to scenarios that lead to pain and injury of the head and neck. Postmortem human subjects, human volunteer testing, and anthropomorphic test device experiments can provide useful information for injury risk assessments, but each method has limitations. Finite element human body models are a useful tool for assessing aviator injury risk and generating data that can be used to improve warfighter safety. This study details the head and neck development for such an HBM, the Incapacitation Prediction for Readiness in Expeditionary Domains: an Integrated Computational Tool (I-PREDICT), through a hierarchical framework. A total of 26 cases were included in the hierarchical validation. The validation framework began with identifying and implementing appropriate material models, assessments of functional spinal units (FSUs), progressing to the regional cervical spine and head, and culminated with assessments of the head–neck complex using the BioRank biofidelity scoring system. I-PREDICT FSUs had an overall excellent biofidelity score when assessed in extension, flexion, and tension. The head had an overall excellent biofidelity score when assessed with impacts to the frontal, maxilla, zygomatic, temporal, and parietal regions. The regional cervical spine had an overall good biofidelity score when assessed in compression, extension, flexion, lateral bending, and axial rotation. The head–neck complex had an overall good biofidelity score when assessed in tension, a head drop case, and a rear impact case. The current I-PREDICT model is designed for a 50th percentile male warfighter.</p>