"Ufimtsev has shown us how to create computer software to accurately calculate the radar cross section of a given configuration, as long as it's in two dimensions," Denys told me. "We can break down an airplane into thousands of flat triangular shapes, add up their individual radar signatures, and get a precise total of the radar cross section."
Why only two dimensions and why only flat plates? Simply because, as Denys later noted, it was 1975 and computers weren't yet sufficiently powerful in storage and memory capacity to allow for three-dimensional designs, or rounded shapes, which demanded enormous numbers of additional calculations. The new gneeration of supercomputers, which can compute a billion bits of information in a second is the reason why the B-2 bomber, with it's rounded surfaces, was designed entirely by computer computations.
Denys's idea was to compute the radar cross section of an airplane by dividiing it into a series of flat triangles. Each triangle had three separate points and required individual calculations for each point by utilizing Ufimtsev's calculations. The result was called "faceting"--creating a three-dimensional airplane design out of a collection of flat sheets or panels, similar to cutting a diamond into sharp-edged slices.