Rockwell X-31 The X-31 was a very special airplane. It had three paddles in the back, which made the exhaust move in the way that they wanted too. It could make very tight turns, because of thrust vectoring. The X-31 was fairly quick, going about 900 mph, or Mach 2.28. The X-31 preformed very well, and was flew many flights. The X-31 was made by a German group. It flew over 500 experimental flights during the era it flew. It worked very well, and they based quite a few airplanes off it. For example, the F-22 uses thrust vectoring!