Summary of the VHITAL Thruster Technology Demonstration Program: A Two-Stage Bismuth-Fed Very High Specific Impulse TAL

The Very High Specific Impulse Thruster with Anode Layer (VHITAL) program has successfully resurrected the two-stage bismuth fueled thruster with anode layer (TAL) technology. The two-stage technology was developed over 25 years ago in Russia, at that time demonstrating specific impulses up to 800 0s at efficiencies greater than 70%. The technology offers a unique combination of previousl y demonstrated performance, throttle- ability and low mass propellant system attributes t hat are attractive for a wide range of NASA missions. The VHITAL program has led the design, fabrication, and test of the VHITAL-160 thruster, a two-stage 160mm accelerating channel TAL with a radiative