The complexity and functionality of high fidelity infrared (IR) aircraft models has increased significantly with each generation. This increase has caused greater stress on scene generation systems to render images at the required HITL frame rates especially for the older systems. The simplest and most cost effective solution is to optimize the rendering software, in this case Real Time CHAMP (RTC). The software modifications fell into four categories: culling to avoid IR calculation on non displayed facets and removing them from the graphics flow; using optimized graphic operations where possible; moving redundant CPU operations into the graphics pipe; and changing coordinate systems to minimize the number of point and vector transformations required. As a result, the rendering rate was doubled for complex multi-plume aircraft models. The increased performance was verified on Intel PC and SGI Onyx2 hardware platforms.