X15 and X1
A pair of "X" planes from the heyday of highspeed research at Muroc/Edwards.
The Revell 1:32 X-1 on the right is an older kit and fairly simple. I finshed it in a single weekend. The Special Hobby 1:32 X-15A-2 is a modern multimedia kit that includes injection molded parts, resin and photoetch.