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The Ultra Compact Combustor (UCC) has shown viable merit for significantly improving gas turbine combustor performance. This concept combines a trapped-vortex approach with a circumferential cavity utilizing buoyancy and high g-loading to improve efficiency and reduce combustor size. Models for small engines can provide g-loading up to 4,000 g’s. However, as the scale of the combustor increases, the g-loading will necessarily decrease. Thus, the importance of understanding the effect of g-loading is pivotal to the applicability of this design to larger engine diameters. The Air Force Institute of Technology’s Combustion Optimization and Analysis Laser (COAL) laboratory studied this effect with sectional models of the UCC. By using both straight and curved sections of the radial cavity, the g-loading can be varied from 0–15,000 g’s. Particle Image Velocimetry (PIV) was used for velocity fields and turbulence statistics. Two-line Planar Laser-Induced Fluorescence (PLIF) of the hydroxyl (OH) radical was used for 2-D temperature profiles. Single-line PLIF was also used for flame location where OH concentrations were too low for temperature determination. Several cases were studied with varying both the equivalence ratio and the main/cavity mass flow ratio. Through the synthesis of velocity fields, temperature and flame location PLIF data, the effect of g-loading was accurately characterized. The immense radial acceleration acts to significantly increase the turbulent intensity present in the combusting regions. This increased turbulent intensity resulted in increased mixing and subsequently a significantly increased flame speed causing a reduced chemistry time. Because the chemistry time was reduced, there was less OH present in the main flow for the high g-load cases due to the combustion process being significantly further progressed when the cavity flow mixes with the main flow.