At the moment, this is dead code: only the tests are compiled. FG is still compiled without this code.
A new directory is created that contains all the numerical computations made to estimate the wake induced by AI aircrafts. This is based on the venerable Vortex Lattice Method (VLM) which was all the rage in the 60's Computational Fluid Dynamics (CFD).
Even though quite old, the method is relevant to compute aircrafts wake in real time since 3D Navier-Stokes (NS3D) is out of reach for real time computations even with modern multicore personal computers and their GPUs.