Tashengurt as mentioned in TEEEJs link many of the Bomb aimers used string and chinagraph marks instead of the wooden sight. One of the documentaries recently possibly the channel 4 Dambusters: Building the Bouncing Bomb. demonstrated how they did it. Apparently the string method ensured that the same eye position was maintained to the air frame, which the wooden one didn't and which was enough to put the bomb off target.
See here second photo.
BBC Radio 2 - RAF Scampton photo tour
Last edited by Windy Militant; 17th May 2013 at 08:03.
Reason: adding link