Something else to consider is altitude and Indicated Air Speed. When you are looking at the HUD or the "speedometer" on the panel, it is giving you Indicated Air Speed. If you look at the E6B, it will show you what your true air speed is. If you look at the speed charts for the TU2, you will see that your should be getting much higher than 190, but again that is True Air Speed, not Indicated Air Speed. The higher you are, the bigger the difference between IAS and TAS.
If you recorded the mission, you can see what your TAS was at that time.