Each model personally signed By Brig. General Chales E. Yeager across one wing.
General (then Maj.) Charles E. Yeager made a number of test flights in this research plane. THe X-4 was designed to test the tailless, or semi-tailless, configuration at transonic speeds of approximately Mach .85.
Each Handcrafted museum quality aircraft replica includes a color photograph and a Certificate of Authenticity.