Hopelessly impossible adjustment: Thrust angle!

As mentioned before, it is impossible and hopeless to keep the thrust angle at Zero degree by measurement and adjustment.

The captain of a light airplane that does not have an automatic device by a computer, adjusts his trim according to his own feeling, and in the case of an airplane that flies horizontally, the opponent is air and must be balanced three-dimensionally. On the other hand, in the case of vehicles, it is friction with the road surface with slipping resistor and is balanced on a two-dimensional plane.

To be honest, I took a sneak peek at the measurement and adjustment of the thrust while considering them, and when I actually went into the scenery, there were many uncertainties, and I had an incredibly furious difficulty in the working. And it was not something that an outsider amateur could do, far from reality!

As a result of more than 20 years of insistent and repeated trial and error, I have experienced more than 10 different cars while that time and finally came close to be able to do something like that recently.

When measured several hours after the start of the measurement, I also took several years to figure out why the data was deviated so much, but this was mainly due to spot deformation of the tires parked in a place for long period of time. I learned that this effect could be dealt with by increasing the tire pressure for convenience.

Even if the thrust angle is brought to zero at that moment from the state where it exists, he has all kinds of bushes, including the release of pressure displacement and the change and wear of the tire ground surfaces, and other fluctuations occur, which cannot be achieved only by one measurement and  adjustment. 

It's a barren world that has to be repeated endlessly.