The invention and adoption of new manufacturing technologies is arguably critical to maintaining national competitiveness in civil and military aviation. We identify two intertwined problems facing policymakers who seek to expedite adoption of metallic additive manufacturing (MAM) in aviation without compromising safety. First, there is as yet insufficient ability to reliably predict the mechanical properties of MAM-produced parts. Second, consensus standards do not yet exist to adequately control MAM processes for safety-critical components, or to economically and reliably test finished parts. In response, we recommend, first, that policymakers fund and steward the collection and dissemination of the data needed to advance MAM from art to science. Second, strategies must be developed to allow industry to learn by doing: for example, by applying MAM to general aviation.  Third, we urge a flexible regulatory posture; perhaps by subjecting rules to sunset clauses that require a substantial rethink at a specified future time.