Why level bombing magnified small aiming errors

A bomb's horizontal motion and accelerating fall create a long parabolic path from aircraft to target. At 200 knots an aircraft covers more than 300 feet each second, so placing a bomb in a thirty-foot target area would require release timing accurate to roughly one twentieth of a second. A bombsight also depended on correct wind, altitude, pressure, speed, and aircraft alignment, while even a one-degree directional error could move the impact by about a hundred feet. A 1941 figure captures the accumulated uncertainty: only seven percent of bombs aimed at the Ruhr landed within five miles of their targets.