JP-900 is a generic name representing a future jet fuel that will be required to handle the anticipated thermal stress of similar to 900 degrees F (482 degrees C) for several hours. In the previous paper in this journal, we showed that the addition, to a JP-8 fuel, of model compounds structurally similar to those potentially derived from the hydrotreatment of refined chemical oil/light cycle oil (RCO/LCO) blends enhances both the thermal oxidative and pyrolytic stability in a flow rig under approximate JP-900 conditions. In this paper, we report model studies designed to clarify the mechanisms by which the model stabilizers (tetralin, alpha-tetralol, and alpha-tetralone) function at 250 and 425 degrees C.