Multiscale or multi-physics modeling play a major role in many important problems today. In the past few years, there have been increasingly growing research activities aiming at developing novel multiscale computational methods. In this work, we focus on one challenge multiscale heterogeneous problem, modeling electromagnetic wave scattering from a composite unmanned aerial vehicle (UAV). Two new computational electromagnetic methods have been developed. One is based on homogenization theory and considers the microscopically heterogeneous system to be a macroscopically homogeneous system by averaging our the fine scales. The other method is to model the full system with complex scale interactions using a novel finite element based multilevel domain decomposition method. Numerical results calculated from these two methods agree very well with each other, which verify the effectiveness and accuracy of both of the two methods.