HUGH W. COLEMAN, PhD, PE, holds the Eminent Scholar Chair in Propulsion and is a professor of mechanical engineering at the University of Alabama in Huntsville. Dr. Coleman holds advanced degrees in mechanical engineering from Stanford University and is a fellow of the American Society of Mechanical Engineers and an associate fellow of the American Institute of Aeronautics and Astronautics (AIAA). He has served on uncertainty standards writing committees for the NATO Advisory Group for Aerospace Research and Development and the AIAA.

W. GLENN STEELE, PhD, PE, is a William L. Giles Distinguished Professor and head of the Department of Mechanical Engineering at Mississippi State University. Dr. Steele holds advanced degrees in mechanical engineering from North Carolina State University and is a fellow of the American Society of Mechanical Engineers and an associate fellow of the American Institute of Aeronautics and Astronautics. He has served on uncertainty standards writing committees for the ISO, the Society of Automotive Engineers-Aerospace, and the ASME.