During the 1980s OH8OS built a rotatable stack system on 20m that was truly impressive. As best as I can recall from a technical report, the array contained 48 or 64 elements (I can't remember which)
OH8OS's array had a total of SIX 6L KLM 20M Yagis--so the right answer is 36 elements. The big amp also helped make it even louder. Somewhere in the chaos of my move to Texas I have some photos of th