This report documents an experiment to determine the training effectiveness of a microcomputer-based avionics system trainer as a cost-effective alternative to training in the actual aircraft. Participants--26 operationally qualified C-141 pilots with no prior knowledge of the Fuel Saving Advisory System (FSAS), a computerized fuel management system for C-141 and C-5A aircraft--were randomly assigned either to an experimental group to receive training on the FSAS via the microcomputer-based, self-tutorial trainer or to a control group to be trained by an instructor on the flight deck of an FSAS-equipped C-141 aircraft. Both groups were trained to criterion proficiency on eight basic FSAS tasks, and time required to achieve proficiency was measured for all subjects on all tasks. As a result of training, the experimental group achieved a mean proficiency rating across the eight tasks which was significantly superior to that of the control group. Moreover, a transfer effectiveness ratio applied to assess transfer of training from the experimental trainer to the criterion task in the aircraft indicated the experimental trainer was fully as effective as aircraft training for the tasks and yielded a cost benefit ratio of 4.76 to 1 (aircraft training cost versus microcomputer trainer cost), which demonstrates the potential benefit of the experimental trainer to reduce training cost. Additional data are presented in two tables, and references are provided. The trainer tryout questionnaire and cost data documentation are appended. (Author/KM)