excellent Kyle much to my surprise the following worked
The Zoom function isn't really actually a zoom function, either, actually (surprise). The + and - keys are referenced by FSX as "increase selection" or "decrease selection." In most cases, someone has pressed a button to select something (like a key for sim rate, or something similar) and the sim still has that selection "focused." Check your commands for overlaps and remove them. You might have a key command for the plane that's overlapping a sim command that utilizes +/- for something else (stealing the focus from the zoom function).