Abstract: A tow sub that has a bullet-shaped shell to cover the front of a diver. The shell is large enough to be comfortable for a diver lying in the shell. The shell has lenses that provide ample vision for the diver. The tow sub has two independent control surfaces. The first, is a fixed dive plane that can be attached to the top, sides or bottom of the shell. This dive plane acts as a diving plane. The second is a pivoting rear elevator control surface that is mounted on a tail boom. The pivoting elevator is controlled from within the shell by a yoke controller. The tow sub has a tow hook that has a quick release mechanism. Using this mechanism, the diver can disconnect the sub from the tow line from within the shell. When disconnected in this way, the sub stops and slowly rises to the surface.

Abstract: A plasma source uses radio frequency electromagnetic radiation to ionize and dissociate gas molecules into reactive species within a plasma generation tube and emits the species to react with and remove contaminants from surfaces on a spacecraft. The source of the radiation is an antenna brazed to the outside of the plasma generation tube. Permanent magnets ring the plasma generation tube within a metallic housing to generate a magnetic field. Pole pieces are provided to improve the strength of the field and to improve its uniformity and axial orientation within the plasma generation tube. A plenum and a gas diffusing element distribute gas entering the plasma generation tube.

Abstract: Apparatus and a method are disclosed to enable on-line modification and upgrading of terminal software in a communication network while maintaining the integrity of communication between a service provider and a subscriber using the network. Software is downloaded on a booter channel on the communication network. A subscriber terminal, coupled to the network initiates a communication with the network to receive downloaded booter data. The downloaded data is stored, and a checksum is computed from at least a portion of the downloaded data. The checksum is tested for validity, and control of the subscriber terminal is released to the downloaded software only if the checksum is valid.