i guess i could be a similar feature to what we use on the CRJ
it is used to find the optimal seat, or eye refernce, position.
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Photo © Martin Boschhuizen - AirTeamImages
the three "balls" form a triangle, with the center white ball sitting a few centimeters in front of the others.
The correct position is obtained by adjusting your seat, so that the red ball covers the white ball ( or the other way around, depending on what ball comes first).
the resulting eye level should be appr. in the center of the forward windshield.
or you just adjust your seat, so you sit comfortable...
hope that helps,
That's it! You people have stood in my way long enough. I'm going to clown college!