For a sense of the problem, watch this Norden bombsight training film.[1] This shows a training mission; the geometry of dropping a bomb with the sight is covered in [2].  Three&#x27;s lots of looking at crosshairs while making fine adjustments to knobs.  It&#x27;s not enough to get the crosshairs on target; approach and drift speeds have to be set so that the crosshairs stay on target as the plane moves.  This is a four-knob job; basically X, Y, dX, and dY. All this has to be done in an airplane, often while people are shooting at you from the ground or attacking the bomber with fighters. The aircraft had to be flown straight and level for a minute or so approaching the target while the bombardier adjusted all the knobs.  That seldom happened in combat against any defended target.<p>[1] <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=DlW-JCqGkYo" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=DlW-JCqGkYo</a>
[2] <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=Eh3hknntD10" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=Eh3hknntD10</a>