I believe the Nimrod aiming system was based on the CVBS - if BEagle be following he was a expert on this.
Basically a vertical chinagraph line on the windscreen and a couple of horizontal lines on a transparent back plate. The vertical was aligned with the target and aimed off for drift. The horizontals to determine range release point.
I don't know if this was the same used on the Nimrod with 20 years of development incorporated
And CVBS? Copilot's Visual Bombing System
