04/30/2008. Remarks by Walter van Tilborg: "The unusual configuration homebuilt N.F.2 Aster*X II was designed and built by Messrs. Rudolf Nickel and Joseph Foucard (hence N.F.2). The one-of-a-kind two-seater first flew in 1994 and it had been preceded by the very similar N.F.1 Aster*X. Both aircraft had a so called pivoting wing which could move in all directions for lateral and longitudinal control (a system also used in the Spratt Controlwing designs.
F-PRUD was powered by one 64 hp Rotax 582 two-stroke engine while the earlier N.F.1 Aster*X (F-PYHG s/n 001) of 1987 had one 36 hp Citroen
V-06-630 car engine. Another difference was that the N.F.1 had a T-tail and the N.F.2 a low-set tail plane.
A third example is the RN.3 Aster*X III of 2004, built by Rudolf Nickel. This aircraft differed in having a tricycle gear and it is not carrying an F-P... registration as it was classified as (French rules) ultra-light."