Escape Dynamics primary objective is to develop a rapidly reusable, single-stage-to-orbit (SSTO) launch system and introduce space access solutions to customers at a price point 10x below the cost of current alternatives.
Escape Dynamics recently completed tests where propulsion was generated using microwaves.
Escape Dynamics is developing external microwave propulsion technology that allows reusable single-state-to-orbit space flight. In external propulsion all or part of the energy necessary for launch is coming from the ground in the form of a focused microwave beam allowing a dramatic increase in efficiency of propulsion compared to chemical rockets and enabling engines with specific impulse above 750 seconds.
Escape Dynamics’ baseline technology uses a wireless energy transfer system based on millimeter-wave high power microwave sources. The baseline frequency is 92 GHz; however, other mm-wave frequencies (90-170GHz) are also considered. The energy is delivered to the moving vehicle via a phased array of antennas enclosed in proprietary side-lobe suppressing radomes, which ensure safety of the energy transfer.
Our baseline propulsion approach is a thermal thruster which uses hydrogen as a working fluid and a heat exchanger for coupling external microwave energy into the thermal energy of the hydrogen. External microwave energy is absorbed in a ceramic matrix composite (CMC) heat exchanger with dimensions of approximately 3meters by 5meters. The hydrogen is initially stored as a liquid in a cryogenic tank and is supplied to the heat exchanger via a turbopump designed to raise the hydrogen’s pressure to approximately 150atm. The hydrogen is heated to above 2000C as it flows through the heat exchanger and is exhausted through an aerospike nozzle optimized for a SSTO flight. The heat exchanger also serves as a primary component of the thermal protection system (TPS) during the return from orbit.
The specific impulse of 750-850 seconds is consistent with single-stage-to-orbit operation and allows for a propellant mass fraction below 72% thereby enabling a path to full and rapid reusability. Our thermal thruster approach allows useful payload fractions between approximately 8% and 12%. In comparison, chemical rockets today are limited to Isp of approximately 450 seconds, are completely or partially expandable, and typically operate with useful payload fractions of 1.5%-3%.Read more »
Escape Dynamics is also developing a next generation system, which relies on the direct heating of plasmas flowing through a resonant cavity with a weight similar to that of the weight of the heat exchanger in a thermal thruster. The goal of this development is to allow operation with specific impulse above 1,500 seconds, leading to propellant mass fraction below 50%, which is comparable to airplanes
