More info:<p><a href="http://en.wikipedia.org/wiki/Kerrison_Predictor" rel="nofollow">http://en.wikipedia.org/wiki/Kerrison_Predictor</a><p><a href="http://en.wikipedia.org/wiki/Tachymetric_anti-aircraft_fire_control_system" rel="nofollow">http://en.wikipedia.org/wiki/Tachymetric_anti-aircraft_fire_...</a>