Propulsion apparatus and method using boil-off gas from a cryogenic liquid

摘要

A propulsion system and method is disclosed for controlling the attitude and drag of a space vehicle (10). A helium dewar (12) contains liquid helium (11) which cools an experiment package (22). The helium is heated or vented to keep the temperature between 1.5 and 1.7 degrees K to maintain helium boil-off gas adequate as a propellant without adversely affecting the experiment package which is contained in the helium dewar for protection from solar heating. The apparatus includes auxiliary heater (32) and temperature sensor (30) for controlling the temperature of the helium. The boil-off gas propellant is delivered to thruster modules (A) to control vehicle attitude and compensate for drag.