This paper describes a study to understand the use of analogies by design engineers with different levels of experience in an adaptive design domain. Protocol analyses of 12 design engineers have been analyzed to understand the functions and reasoning of the analogies. The protocols are real-world data from the aerospace industry. The findings indicate a significant difference in both the use of analogies by novices and experienced designers and the reasoning from the analogies. Novices were found to predominantly transfer information related to the geometric properties without explicit reference to relevant design issues or to the appropriateness of applying the analogy, whereas experienced designers tended to use analogies for problem solving and problem identification. Experienced designers were found to use the analogy to reason about the function of a component and the predicted behavior of the component, whereas the novices seem to lack such reasoning processes.