WWII RAF Navigator's Compass

[browningautorifle]

Is there a way of setting the declination

Given that I don't know of too many aircraft in WWII that sat level on the tarmac

Remember it's going to be used when they are in level flight, not for shooting a bearing through the bamboo. Considering the examples seen including yours and the others in the links...the indicator sits directly on the north indices. The navigator has to do some math.

I understood that a lot of the RAF stuff like calibrated instruments was all sent back to the UK for repair etc to the manufacturers for certification.

I guess that makes the most sense. Our guys do handle instruments but I'd have to find out how deep that would go.