14 C.F.R. § 29.737 Skis.
Title 14 - Aeronautics and Space
(a) The maximum limit load rating of each ski must equal or exceed the maximum limit load determined under the applicable ground load requirements of this part. (b) There must be a stabilizing means to maintain the ski in an appropriate position during flight. This means must have enough strength to withstand the maximum aerodynamic and inertia loads on the ski.
Title 14: Aeronautics and Space
PART 29—AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT
Subpart D—Design and Construction
Landing Gear
§ 29.737 Skis.