The High Power Helicon Thruster is an electrodeless plasma source able run at kW to 100s of kW to produce thrust levels as high as several Newtons of force with high power and gas effciencies. Helicon plasmas can be generated without the use of grids and electrodes, reducing concerns of wall erosion. The plasma itself is generated through high power radio frequency waves that allow substantial flexibility in operational characteristics. The device is much smaller than similar power level thusters which adds to its versatility.
Human exploration and fast missions to the outer planets will require plasma thruster operating in power regimes > 100 kW. For electric propulsion, such a regime can only be attained by increasing the size of the thruster or through an array of thrusters. The intent of the Double Gun experiment is to examine whether an array of High-Power Helicon Thrusters passing through a single large nozzle magnet downstream can lead to efficiencies greater than an individual system.