14 C.F.R. § 27.871 Leveling marks.
Title 14 - Aeronautics and Space
There must be reference marks for leveling the rotorcraft on the ground.
Title 14: Aeronautics and Space
PART 27—AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT
Subpart D—Design and Construction
Miscellaneous
§ 27.871 Leveling marks.
