The model aircraft has no wheels when flying, but does after being placed on the table.
Waverly admits that he sabotaged the roof laser because he didn't want any harm to come to Hemingway, his brother in law. But the laser would have only destroyed the model plane, not Mr. Hemingway, who was on the ground and a far distance from U.N.C.L.E. headquarters.
Illya and Solo rushing out of the office is the same shot from "The Green Opal Affair" as evidenced by the wooden block hanging from the ceiling that Kuryakin was swinging at with a baseball bat.
When Riley is trying to escape by running into the elevator, the floor is in view and it shows no break between the hallway, revealing that the "elevator" was simply just another room instead of a real elevator.
When Solo & Kuryakin climb down the elevator cables, the cables not only look like rope, they are slack instead of taut and move in a way that clearly shows that they are made of fiber, not steel.
The "remote controller" for the model airplane is just a Motorola TV rabbit ear set attached to a board. The Motorola "M" logo can be seen on the plastic case of the antenna assembly.
When the model plane is approaching UNCLE headquarters it appears to be motionless and swaying slightly as if it is just suspended by a string.