1. Senior Turbomachinery Engineer, Propulsion, 1 Rocket Rd., Hawthorne, CA 90250; Space Exploration Technologies, Hawthorne, CA 90250; formerly, The Aerospace Corporation, El Segundo, CA 90245
2. Engineering Specialist, Fluid Mechanics Dept., P.O. Box 92957, Los Angeles, CA 90009-2957; and The Aerospace Corporation, El Segundo, CA 90245 (corresponding author).