Which shape is known to give the greatest RADAR Cross Section (RCS)?

The choice of a corner reflector as the shape that provides the greatest RADAR Cross Section (RCS) is accurate because of its unique geometric properties that enhance radar reflection. A corner reflector is essentially formed by three mutually perpendicular flat surfaces, akin to the corner of a box. When radar waves hit a corner reflector, they bounce off the surfaces in a way that redirects a substantial portion of the energy back towards the source of the radar.

This design allows for maximum reflection of radar signals due to the constructive interference of the reflected waves. The shape effectively traps the incoming radar energy, making it appear larger to the radar system than it physically is. This characteristic leads to a significantly higher RCS compared to other shapes, which do not possess the same capability to redirect radar waves effectively.

On the other hand, shapes such as flat plates, cones, and spheres, while they can have RCS, do not possess the same reflective and directional properties that a corner reflector does. Flat plates can reflect radar waves but are often better for specific angles rather than across a wide range. Cones do not provide the same backward reflection characteristics, and while spheres can scatter radar waves, they do not concentrate reflections back to the source as effectively as corner reflectors do.