If we are now talking airfields in Germany with great aircraft museums, I can thoroughly recommend Speyer. And it's nearer to Elstree than Dornoch in Scotland, another airfield with a nice beach nearby.
Sinsheim has a similar museum to Speyer but is a little further away from the airfield, I understand. For a more modest aviation, but very friendly family, museum on an airfield in the Black Forest, try Schwenningen (EDTS).