R68-15 Trajectory Computation by a Hybrid Computer for the Apollo Midcourse Abort Simulation

The paper by Smith is representative of a class of spacecraft-guided simulation problems wherein the body dynamics of the spacecraft are eliminated by assuming that the inertia of the body is zero. Thus rotational accelerations become infinite and attitude system-response times are taken to be zero. The simulation of such problems is most generally performed entirely on digital equipment because the rate of change of the guidance function is generally of the same order as the rate of change of the trajectory parameters.