The two aircraft models in Wentworth's home are a twin-engine J1N1 Gekko Type 11 and a J2M3 Raiden. While the BVD-100 was fictitious, BVD existed, a consortium of aircraft makers Boeing, Vega (Lockheed) and Douglas, formed to build Boeing B-17 assemblies in several locations.
When Ellery is explaining the clue of the door key, he says that a local hardware store loaned him the miniature door on which he demonstrates. Actually the miniature door is the one used in other episodes by the sound effects men for "The Casebook of Simon Brimmer".