Mich. Comp. Laws § 259.482d

Sec. 2d. (1) Except as provided in subsection (2), a runway's transitional surface extends to the intersection of the transitional surface with the horizontal surface. (2) For a runway that has a precision instrument approach, the transitional surface beginning at the side of a runway's approach surface extends for 5,000 feet measured horizontally from the side of the approach surface.