The detection of objects by radars is essential for civil applications such as coastal surveillance (detection of ships or oil slicks) and air traffic control (detection of aircraft), and also for military applications (detection of drones). To recover necessary information on the target (position, size, materials, shape), it is mandatory to accurately model the path of the wave emitted by the radar to the object. Therefore, many phenomena must be considered, such as refraction, relief, and ground composition. This is also useful for optimizing an antenna's position or mitigating the effect of man-made structures such as wind turbines or solar panels. In this context, the work presented here focuses on several hybrid models for calculating the radar cross section (RCS) of metallic targets in a maritime environment. The latter is based on a hybridization between two methods. First, the parabolic wave equation (PWE) solved in the wavelet domain is considered to propagate from the source to the target. Its main advantage is its ability to consider, over long distances, the relief (waves, islands), the effects of refraction within the propagation channel, and the ground composition. Second, we hybridize the PWE with different integral equation-based methods to account for the target and compute its RCS. To achieve this, the methods used here are physical optics and physical diffraction theory, which, being asymptotic, have the advantage of being fast, as well as the method of moments, which, being an integral equation method, takes more time but gives more accurate RCS values. The computation time is nevertheless accelerated by using a wavelet basis, which also improves the conditioning of the matrix. Numerical experiments in the VHF band are carried out to validate and compare the different hybrid models.