The fleet performance of a small group of Project 100,000 (low aptitude) personnel was assessed by means of an evaluation form completed by their supervisors after the men had been on board for approximately seven months. The men had previously been trained for the Navy rating, Aviation Structural Mechanic S (Structures), AMS. The performance of other personnel working in the AMS rating, who had been attached to the same squadron for a comparable period, also was assessed for purposes of comparison. Statistically significant differences between the two groups were not found, although all measures showed a small difference favoring those who were compared with the low aptitude personnel. The performance of Project 100,000 personnel in the AMS rating ranged from above average to satisfactory. On the whole, the study suggests that the use of Project 100,000 personnel in the AMS rating is not in the best interest of the Navy unless dictated by manpower shortages or other nonmilitary considerations. (Nine tables and eight references are included.) (author/ly)