An evaluation was made of the capabilities and utilization of Group 4 personnel aboard an operational navy vessel (U.S.S. Catskill MCS-1). Assessments were made of a Group 4 sample and a comparison non-Group 4 sample in terms of aptitudes and experience, training achievement, and preliminary shipboard performance. The results indicate that the Group 4 sample had significantly less formal education, lower chronological age, and less enlisted service than the non-Group 4 personnel. The Group 4 sample averaged significantly lower aptitude test scores than the other sample. In addition, more discipline problems and lower supervisory ratings were recorded for the Group 4 sample than for the non-Group 4 sample. (Three references and eight tables are included. See also the followup study, AC 008 698.) (Author/LY)