Thank Manz and Michael but not quite what I was looking for as you can't actually draw objects on the cplane unless the view is cplane. If the view is cplane then my blueprint is orientated at a odd angle due to the odd angle of my cplane. I want to be able to draw in the default top, side or front view onto the cplane.

I'll explain with this example.
I have an aircraft with blueprints setup in top, front and side views which is all quite normal.
The wing has a angle of incidence of 6 degrees and I want to draw some objects on top of the wing to match my blueprints so I angle my cplane to wing (6 deg). My blueprints are then at a odd angle and I can't draw the objects accurately on top of the wing due to the bad orientation of my blueprints. If I could remain in the default top view (not cplane top view) and still draw objects on the cplane would be perfect.
Hopefully this explaination is clearer ?

PS I didn't know you can set up additional blueprints using the cplane so this is a workaround solution but when modelling all sorts of stuff at odd angles to each other it will be tedious process setting up blueprints all the time not to mention managing all the blueprints.