Abstract: A vortex flow field and an apparatus and a method to produce and sustain it. The flow field includes an outer fluid vortex spiraling toward a closed end of the flow field generating apparatus and an inner fluid vortex substantially concentric with the outer vortex spiraling away from the closed end and toward an outlet opening in which the inner vortex spirals in the same direction as the outer vortex, but in the opposite axial direction. The invention also relates to a rocket propulsion system utilizing the flow field in which the propulsion system includes a combustion chamber with a fuel source and an oxidizer source flowing along the flow field.

Abstract: A cryogenic solid hybrid engine with a solid propellant chamber, a first propellant within such chamber in which the first propellant is in solid form in the chamber and is in fluid form at room temperature, a coolant fluid chamber and a coolant fluid in the coolant fluid chamber being maintained at a temperature blow the freezing point of the first propellant. The invention also relates to a method for propelling a rocket and a method for forming a solid propellant grain for use in a cryogenic solid hybrid rocket engine.

Abstract: A rotation sensor utilizing light reflection and/or refraction techniques including a light source, a light reflecting surface and a reflected light receiving member in which the elements are positioned so that the intensity of light reflected by the reflecting surface and received by the receiving member is unique for each rotational position being measured. The invention also relates to a method utilizing the above sensor.