Some possible reasons:
-you're not at constant speed and level flight. Hit X and fly level for at least on sector before you begin to cal your sight.
Thats what I do (with all bombers, but particularily with the heavy ones and Arado).
-Pick your target which has to be at least 3 or 4 sectors or even more if youre flying a slow-climber, away from your take-off AF.
-climb to desired alt
-align with target at least 2 sectors ahead of target area
-Play with throttle until you have constant airspeed. This should be about 1,5 sectors ahead of target.
-Open bomb-bay at least 1.5 sectors ahead of target, since it induces drag and will slow you down. The heavier the bomber, the longer it takes to reach constant speed again.
-as soon as you see the target area, hit U and zoom ALL the way in to a recognizable calibration spot on target.
-Hit Y as soon as you are sure you can maintain a constant track for your joystick setting, and hold down for at least 10 seconds.
-RELEASE Y, BUT DONT release on Joystick BEFORE that. I.e. Maintain steady track, and concentrate on releasing Y WHILE maintaining your tracking.
-Hit U
-zoom out
-adjust flight direction while still on bombsight, and ONLY there.
You should be able to hit where you calibrated.
Hope this helps!
Matt
