Most modern torch drives use a specialized fusion method known as sheared-flow stabilized Z-pinch fusion, in which a bolt of electricity is dumped into the fuel plasma, generating a very powerful axial magnetic field. This field crushes the plasma to incredible densities until it fuses, in brief pulses happening several times per second. Rather than attempting to confine the plasma within a magnetic bottle, the plasma is instead allowed to flow axially down the length of the reaction chamber. This mutes the various instabilities that arise in other Z-pinch devices. This also makes it a very convenient rocket engine, as channeling the resultant plasma stream out of one end with a magnetic nozzle can generate significant thrust. Magnetohydrodynamic generators bleed off a small portion of the plume’s energy to recharge the supercapacitor banks for the next fusion pulse. Due to the large flux of thermal and neutron radiation from the star-hot fusion plasma, torch drives are an open cage of magnetic coils and filigree-like truss work in order to let the majority of the radiation escape into space rather than be absorbed by the engine. In addition, the delicate superconducting coils are protected from direct exposure to the fusion plasma by thin, knife-like blade shields. These coils must be kept cool in order to remain superconducting. The shields present their knife-edges towards the plasma stream, absorbing a small margin of radiation while scattering the rest. Their extremely thin cross-section means that they have a very large surface area, and thus function as passive radiators. As such, tungsten is the material of choice, being able to heat up to nearly 3000 K before beginning to sublimate. The blades are placed at a standoff distance of 2 or 3 meters from the plasma itself, with the tips just barely below the sublimation point. Ironically, the blade shields and radiators of a torch drive are often far brighter than the exhaust plume, often glowing at around 2800 K (as bright as early incandescent light bulbs).