Why does beam end before target when using source tangent?

I’m trying to create a parabolic beam similar to the one mentioned in this [other question][2]. In fact, I’m even using the method on that other question to calculate my parabola and to determine the source and target tangents.

The problem I’m running into is that if I don’t set source and target tangents, the beam travels perfectly as expected in a straight line from source to target. But if I do set source and target tangents, the beam looks like it’s kinda starting to follow the parabola but then sorta ends in space halfway along it’s journey.

I’ve verified that the beam distance property is sufficiently high (5000) and can’t think of any other reason that the beam can’t make it the full distance to it’s target.

Here’s where things stand now:

86924-capture.png

Red is desired parabolic path

Yellow is direct line from source to target

Blue is the actual beam