For range safety purposes, it is necessary to know the capability of an Atlas missile to change the direction of its velocity vector. The mechanism of this change could be autopilot or control system failure, the result being that the engines are locked in some arbitrary fashion so as to produce a turn. The flight characteristics of an Atlas are such that a condition like this will cause the missile to tumble. The digital simulation discussed in this report is designed to execute the maneuvers resulting from a swivel angle held constant throughout a tumbling turn. The purpose of this report is to document the simulation and provide information required for its use.