The Effect of Conceptual Diagrams on Aviation Mechanics' Technical Systems Understanding.

A quasi-experimental study explored the effect of functional flow diagrams on technical system understanding. An individualized field training package which contained schematic diagrams that illustrated an aircraft's electrical system was complimented with functional flow diagrams. In a 4-week treatment, a control group of 10 students enrolled in Aircraft Systems II in the Institute of Aviation (University of Illinois at Urbana-Champaign) received the instructional package that contained only schematic diagrams. The treatment group of eight students enrolled in the same course received an instructional package that contained the schematic diagrams and additional conceptual diagrams of the systems. Following each of the four units of instruction, subjects were given unit tests designed around the structure, function, and behavior of the system. T-tests were used to compare test scores. Four subjects from each group were also randomly selected to perform card sorting tasks at the end of each unit. Results showed that use of functional flow diagrams improved overall system understanding related to the electrical systems and improved significantly subjects' ability to reconstruct conceptual models similar to those of an expert. The functional flow diagrams were an effective instructional medium for enhancing students' conceptual understanding of the causal behavior of the system. (Appendixes include 4 tables, and 4 figures.) Contains 38 references. (YLB)