JEWEL B. BARLOW, PhD, is Director of the University of Maryland's Glenn L. Martin Wind Tunnel. He is a former chairman of the Subsonic Aerodynamic Testing Association (SATA). WILLIAM H. RAE, Jr. (deceased) was associate director of the F. K. Kirsten Aeronautical Laboratory at the University of Washington and a charter member of the Subsonic Aerodynamic Testing Association. ALAN POPE is a former director of aerodynamics at Sandia National Laboratory. His other books include High-Speed Wind Tunnel and Wind Tunnel Testing.