ORIGINAL: RAPPTOR
FROM PICS IT LOOKS TO BE ABOUT 15%,, ??? MAYBE WE MEASURE DIFFERNTLY
If you were to measure the total length of the MAC, then measure the distance of the CG on the MAC, you'd find that the CG is at 25% of the MAC. (Acutally, I think it's 23%, but what's 2% among friends, right?)
I always take my wing planforms to the centerline of the aircraft, which isn't shown on the drawing posted above. The MAC location is shown on the starboard wing.
Take a piece of paper and hold the edge up to the MAC. Mark the paper with the MAC, then fold the page so that the MAC is divided in quarters, then compare the folds with the location of the CG and you'll find that the first fold (25%) is just behind the CG shown on the drawing.
When calculating CG, most people make the mistake of only measuring the exposed wing, which is why they might
think the CG is at 15% of the MAC, but unless you include the portion of the wing hidden inside the fuselage, you'll get a false perception of where the MAC is located and where the CG is located on the MAC.
Here's another example of a CG calculation that I did for a MiG-29. I flew my MiG-29 model at the location shown on the drawing below and it flew perfectly.
Notice that the wing planform not only carried to the centerline, but also includes the blended forebody. Failure to do both would almost certainly guarantee that the model will be extremely tail-heavy.
Dan